Chapter 14
Maintenance and Growth Considerations

Congratulations! You've just about reached the goal line. But don't start celebrating quite yet. You still need to keep your eye on the ball as you deploy and then enter the maintenance end zone.

This chapter is divided into two sections. The first provides recommendations surrounding deployment. Then we turn our attention to maintenance issues, starting with checkups to assess the health of your DW/BI system, followed by prescriptive plans to address common sponsorship, usage, architecture, and data maladies. We finish by dealing with the orderly “sunsetting” or preserving of data from legacy applications that are no longer being used by IT.

Deploying Successfully

Deployment demands significant upfront planning prior to the big event. In this section, we discuss the advance preparation required for operations and marketing, as well as considerations when rolling out subsequent projects focused on new business processes.

14.1 Don't Forget the Owner's Manual

Joy Mundy, Intelligent Enterprise, Jul 1, 2005

Data warehouse teams often postpone thinking about the ongoing operations of their new DW/BI systems until they're nearly in production. It's too late to start designing your operating procedures when deployment deadlines are looming and users are clamoring for data and reports. The train has already left the station. You'll be making stuff up as you go along, inevitably making mistakes.

Think about two sets of considerations with respect to the ongoing operations of your production DW/BI systems. The first set revolves around users: What information do they need to use the system successfully? And after the initial launch, how will the system improve and evolve to meet their needs? Second and equally important are the planning considerations for technical systems management: the procedures to ensure the system operates trouble free, or at least crisis free.

Front Room Operations

When a new DW/BI system is deployed, business users focus on the front room: the interface they see and use every day. In fact, user communities sometimes refer to the data warehouse by the BI tool vendor's name or the “reporting portal.” Little do they realize that building and deploying reports is only a fraction, typically less than 10 percent, of the effort required to create a DW/BI system. But people focus on what they can see. If the reporting portal is ugly, uninformative, or slow, the entire warehouse/BI system looks bad.

When launching the BI environment, you'll publish an initial set of reports, charts, and analyses that meet the requirements identified through business user interviews at the beginning of your project. Let's assume these deliverables are meaningful, attractive, parameterized as appropriate, and allow drill-down where useful. You must train the business users on the system you've built: not just where to click, but also how the analyses should be used and why. Here are some typical user questions you must be prepared to answer:

  • How do I access the BI system?
  • How do I request broader system access?
  • How do I find the report I need?
  • When was the data in the system last refreshed?
  • Where can I get help?
  • How do I customize a report?
  • How do I build a completely new report?
  • How do I add my report to the system so others in the organization can use it?
  • How do I customize my portal view?
  • How do I build a more complex analysis?

You might be able to build such an intuitive reporting environment that the answers to some of these questions are obvious, but you're fooling yourself if you think you can avoid documenting the system and providing rollout training.

You must establish (and maintain) a web site with fresh information about how to use the system, data currency, and where to get help. If your reporting tool has a web-based launch page, think about customizing that page to add this important information. Otherwise, train users to go to your page first and link from there to the reports and/or tool page.

You must also develop plans for training after the system is in production. New hires will need training and a surprisingly large percentage of the initial users will benefit from more instruction. Perhaps you'll need to offer new types of training, for superpower users or very occasional users. Online instruction materials are useful, but there are significant benefits to getting business users in a room where you can talk to them, and they can talk to each other, face to face.

Your front room rollout and operations plan should include a plan for the help desk. If your organization has a centralized IT help desk, use the same infrastructure for first-tier support. Even though connectivity is a lot simpler than it was a decade ago, the majority of user issues are still about how to connect. A centralized help desk can help on this front, but plan for a large percentage of questions to get escalated to specialists, probably someone on the data warehouse team.

Many query and reporting tools let business users customize their system views, often by creating “My Reports” folders on the portal. This functionality is great, but you should develop policies and procedures for personal reports warranting higher visibility. It often makes sense for central BI team members to put reports through quality assurance and tweak them before publishing to a broad audience. It's not only a matter of ensuring that new or revised reports are accurate; you must also ensure that they perform well and that modifications won't adversely affect existing users.

Back Room Operations

The second set of considerations focuses on technical systems management. Long before you go into production, you must think about a host of operational concerns because your decisions will affect the system configuration and design. If you don't create a sound operations plan before you deploy, the data warehouse team will end up patching things together in crisis mode, which inevitably leads to crises of confidence within the user community.

The back room operations plan should address at least the following questions:

  • How will you monitor resource usage?
  • How will you report on usage?
  • How will you automate your operations, especially the extract, transformation, and load (ETL) processing?
  • How will you know when your ETL processing has encountered a problem?
  • How will you notify users of data problems?
  • How will you monitor system performance?
  • How will you kill relational database and OLAP system queries?
  • How will you identify and solve performance bottlenecks?
  • How can you tune the system to prevent bottlenecks?
  • How will you ensure your system never runs out of disk space?
  • Do you need to modify your ongoing ETL process to accommodate data partitioning?

Most important, you need to plan, implement, and test your backup and recovery strategy. A backup and recovery plan that's not tested regularly isn't a plan. It's a wish, and it's unrealistic of you to expect that wish to come true.

There are no easy answers to these questions. The best solutions are intertwined with your ETL system design. You can prevent a lot of problems by designing your ETL system to proactively check for conditions, such as the successful completion of an operational process, before starting work. As described in article 11.2, The 34 Subsystems of ETL, a robust ETL system checks for exceptions and whether the data volume and contents are reasonable. Keep track of how much disk space a daily load requires and verify that plenty of disk space is available and allocated.

Monitor Operations

Plan to monitor the operations of all the software components in your DW/BI environment: operating systems, relational databases, OLAP and data mining systems, query and reporting software, and any web portals. Developing a robust monitoring system usually requires combining features of your operating systems with features of your database engines and front end tools. Even if you use a single vendor for your BI technology, you should expect to combine several kinds of monitoring. Plan to create a relational database to store the monitoring performance data. You may populate the results of monitoring traces directly into the relational database, or it may make more sense to trace into files and then load those files periodically.

Monitor the systems at all times. Set up the “always on” monitoring to include important events such as user logons and ETL process completions, in addition to all error events. This “always on” monitoring should periodically record statuses such as memory usage, perhaps at 15-minute intervals. Because this basic monitoring is continuous, you should justify the inclusion of every element you're tracing.

Periodically, perhaps once a month, ratchet up the monitoring to capture more events and statuses. This monthly detailed baseline can be invaluable in diagnosing performance problems, and you can often catch these problems before they're perceptible to business users. You may trace statuses at five- or 15-second intervals and keep detailed track of the processes occurring. Detailed monitoring usually affects system performance, so avoid doing it during system usage peak times. On the other hand, if you monitor the reporting system in the middle of the night, you probably won't learn anything.

These operational issues aren't sexy. You're not going to fire up the imagination of business users by talking about them. But if you don't think about these problems early on and build an operations plan into your procedures, your DW/BI system will fail. Business users won't know how to use the system and they won't know where to go to get information and assistance. Their confidence in the system, the efforts will be shaken. All they'll see is the bad, and the 98 percent of the system that's good will go to waste.

14.2 Let's Improve Our Operating Procedures

Joy Mundy, Design Tip #52, Mar 4, 2004

In my career I've been able to review a lot of data warehouses in various stages of their lifecycles. I've observed that, broadly speaking, we are not very good about operating the data warehouse system with anything like the rigor that the transaction system folks expect of their systems. In all fairness, a data warehouse is not a transaction system, and few companies can justify a 24 x7 service level agreement for data warehouse access. But come on guys, do we have to look like Keystone Kops in an emergency? As we all know, bad things happen, especially in data warehouses, which are downstream from every other system in your company.

Operating a data warehouse in a professional manner is not much different than any other systems operations: Follow standard best practices, plan for disaster, and practice. Here are some basic suggestions, based on my observations from actual deployments.

  • Negotiate a service level agreement (SLA) with the business users. The key here is to negotiate, and then to take that SLA seriously. The decision about service level must be made between the executive sponsor and data warehouse team leader, based on a thoughtful analysis of the costs and benefits of ratcheting up the SLA toward high availability. The basic outlines of the SLA need to be negotiated early in the project, as a requirement for high availability may significantly change the details of your physical architecture. Remember that an SLA is meant to be a reasonable compromise between both parties: IT and the business users. Signing up for “five 9's” of uptime reliability means your data warehouse can only be down for five minutes and 15 seconds per year.
  • Use service accounts for all data warehouse operations. You'd think it would go without saying that all production operations should use a specified service account with appropriate permissions. But I've long lost count of how many times I've seen production loads fail because the DBA left the company and his personal account became inactive.
  • Isolate development from testing from production. Again, it should go without saying. Again, apparently it doesn't. I've observed two main barriers against teams being rigorous about dev/test/prod procedures: cost and complexity.

    The hardware and software costs can be significant, because the best practice is to configure a test system identically to its corresponding production system. You may be able to negotiate reduced software licensing costs for the test system, but the hardware vendors are seldom so accommodating. If you have to skimp on hardware, reduce storage first, testing with a subset of historical data. Next I'd reduce the number of processors. As a last resort, I'd reduce the memory on the test machine. I really hate to make these compromises, because processing and query characteristics might change in a discontinuous fashion. In other words, the test system might behave substantially differently with reduced data, processors, or memory.

    The development hardware systems are usually normal desktop machines, although their software should be virtually identical to test and production. Coerce your software vendors to provide as many development licenses as you need at near zero cost. I think all development licenses should cost less than $100. (Good luck!)

    Everything that you do to the production system should have been designed in the development machine and the deployment script tested on the test system. Every operation in the back room should go through rigorous scripting and testing, whether deploying a new dimensional model, adding a column, changing indexes, changing your aggregate design, modifying a database parameter, backing up, or restoring. Centrally managed front room operations like deploying new query and reporting tools, deploying new corporate reports, and changing security plans, should be equally rigorously tested, and scripted if your front end tools allow it.

    Data warehouse software vendors do not make it easy for you to do the right thing. The front end tools and OLAP servers are particularly bad about helping, or even permitting, the development of scripts for incremental operations. It is very challenging to coordinate the rollout of a new subject area across RDBMS, ETL system, analysis, and reporting systems. Be very careful, and practice, practice, practice!

  • As much as possible, make a data warehouse release be like a commercial software release with a well defined release number and an accurate list of all the components that implement the release. Make it possible to back out a release in order to restore the previous version if the release contains a catastrophic error, such as calculating division profitability incorrectly(!).
  • Develop playbooks for all operations. A playbook contains step-by-step instructions for performing an operation, such as restoring a database or table, or deploying a new dimensional model, or adding a new column to a table. You should develop generic playbooks, and then customize that playbook for each operation you plan to perform in production. For example, if you are changing a database parameter, write down, in reasonable detail, the steps to follow. Then test the playbook on the test system before applying it to the production environment. The playbook is particularly vital if you are performing an operation through a tool's user interface rather than via a script.

Operations is not the fun part of data warehousing. But with good planning and practice, you can meet the inevitable snafus with calm and deliberation, rather than hysteria.

14.3 Marketing the DW/BI System

Warren Thornthwaite, Design Tip #91, May 30, 2007

Marketing is often dismissed by technical folks. When someone says “oh, you must be from marketing,” it's rarely meant as a compliment. This is because we don't really understand what marketing is and why it's important. In this article, we review classic marketing concepts and explore how we can apply them to the DW/BI system.

It might be more palatable to think of marketing as education. Marketers educate consumers about product features and benefits, while generating awareness of a need for those features and benefits. Marketing gets a bad name when it's used to convince consumers of a need that isn't real, or sell a product that doesn't deliver its claimed features and benefits. But that is a different article. Really great marketing, when effectively focused on the value delivered, is hugely important.

Before you start creating your marketing program, you should have a clear understanding of your key messages: What are the mission, vision, and value of your DW/BI system? Marketing 101 has focused on the four Ps (product, price, placement, and promotion) for at least the past 30 years or so. We'll look at each of these factors in the context of the DW/BI system and direct you to additional information where it is available.

Product

As far as the business community is concerned, the DW/BI products are the information needed for decision making and the BI applications and portal through which the information is delivered. Our products must excel in the following five areas:

  • Value. Meet the business needs identified in the requirements process.
  • Functionality. Product must work well.
  • Quality. Data and calculations have to be right.
  • Interface. Be as easy as possible to use and look good.
  • Performance. Deliver results in a reasonable time frame as defined by the users.

Price

Most users don't pay for the DW/BI system directly. The price they pay is the effort it takes to get the information from the DW/BI system compared to other alternatives. There is an upfront cost of learning how to use the BI tool or applications, and an ongoing cost of finding the right report or building the right query for a particular information need. You must lower the price as much as possible by first creating excellent products that are as easy to use as possible. Then offer a full set of training, support, and documentation, including directly accessible business metadata, on an ongoing basis.

Placement

In consumer goods, placement is obvious: The product has to be on the store shelf or the customer can't buy it. For the DW/BI system, placement means our customers are able to find the information they need when they need it. In other words, you must build a navigation structure for the BI applications that makes sense to the business folks. Additionally, tools like search, report metadata descriptions and categories, and personalization capabilities can be extremely helpful. For additional information, take a look at article 13.11, The BI Portal.

Promotion

Every customer contact you have is a marketing opportunity. TV ads are not an option, not counting YouTube, but you do have several promotion channels for the DW/BI system:

  • BI applications. These are what people use the most. Names are important; having a good acronym for the DW/BI system can leave a good impression. Every report and application should have a footer indicating that it came from the DW/BI system and a logo in one of the upper corners. Ultimately, if you create a good product, the name and logo of your DW/BI brand will become marks of quality.
  • BI portal. This is the main entry point for the DW/BI system. It has to meet the same requirements as the BI applications.
  • Regular communications. Know who your stakeholders are and which communications vehicle works best for each. Your ongoing communications plan will include status reports, executive briefings, and user newsletters. Consider webcasts on specific topics if that's an option in your organization.
  • Meetings, events, and training. Any public meeting where you can get a few minutes on the agenda is a good thing. Briefly mention a recent successful business use, remind people of the nature and purpose of the DW/BI system, and tell them about any upcoming plans or events. Host your own events, like user forum meetings, every six to nine months or so.

Ongoing marketing is a key element of every successful DW/BI system. The more you keep people informed about the value you provide them, they more they will support your efforts.

14.4 Coping with Growing Pains

Joy Mundy, Intelligent Enterprise, May 1, 2004

So you've deployed your first dimensional model. Fortunately, the business loves it and is clamoring for more! They want to query and analyze integrated data from additional enterprise data sources. For some of you, this demand is a dream come true. For others, it may be the start of a slow motion nightmare.

In this article, I'll use a case study to discuss the challenges you'll likely encounter when it's time to roll your next business process dimensional model into production. Sadly, there's no magic. Putting your next business process subject area into production is a difficult, though not intractable, problem. It's a good place to focus any fastidious tendencies you might have.

Recognize the Target

Let's start at the end state goal. Your target enterprise information architecture consists of multiple interconnecting business process dimensional models sharing conformed dimensions as advocated by the enterprise data warehouse bus architecture approach. Using shared conformed dimensions has several important implications. Durable keys in the dimensions must be identical. How else can you join across subject areas? Additionally, you must have corporate agreement about which attributes are tracked through history and which are updated in place. How else can dimension keys be identical?

Case Study Scenario

Let's imagine you launched your enterprise information infrastructure with a successful retail sales dimensional model. The retail sales information is used daily by store management, as well as by many corporate users in marketing and finance. It captures data at the correct transactional grain, its daily update process is smooth, and system downtime is well within the service level agreement (SLA). The retail sales schema is a thing of grace and beauty.

The success of the retail sales project has emboldened management to extend the enterprise data warehouse to support additional CRM requirements, namely customers' calls into the call center. In theory, this decision is no problem: You'll reuse the date and customer dimensions from the first project, add some new dimensions and new facts, and you're done, right? In practice, there will be a few wrinkles.

Not So Fast

Obviously, you'll need to figure out how to modify the ETL process to also populate the new tables in the call center schema. But there may be some more complex implications.

Let's think a bit more about the customer dimension in the original retail sales schema. First, the definition of a sales customer is actually a subset of all customers; the only customers you know anything about are those with loyalty cards and corresponding account numbers. When you add the call center information, you can expect to get information about a whole group of customers you've never seen before. The customer dimension ETL process is going to have to change to accommodate the new source, as I'll discuss later. Adding new customers to the customer dimension shouldn't affect the existing dimensional model. The new customer rows won't join to any existing retail sales fact rows because there's no way to link a “nonloyalty” caller to a sales transaction. The existing sales schema should behave the same, or almost the same, as it always has.

What if the business users want to track more information for call center customers than was necessary or available for retail sales? For example, what if the caller's phone number is important? You need to add that new attribute to the customer dimension, again modifying the customer dimension ETL process. As was the case with the new customers, adding the phone number shouldn't disrupt the original dimensional model; existing reports and analyses will continue to work as before.

Finally, let's tackle a harder problem. What if the business users of the call center data have a compelling need to track history for the customer's address? In other words, they want to be able to know that when a customer called last year she lived in Montana, but now lives in Hawaii. Dimensional modeling can handle this requirement with the type 2 slowly changing dimension (SCD) technique. The issue is that you're changing a fundamental characteristic of the customer dimension in a way that could affect the existing retail sales dimensional model. I'll return to this dilemma in a bit.

Plan Before You Build

Not surprisingly, the first thing you need to do to deploy the call center data is develop a plan. I hope you already have policies for managing the development cycle: checking in code to source control; using separate development, test, and production environments; having specifications and test plans; deploying SLAs for system availability, and so on. If not, now is a good opportunity to put that infrastructure in place.

The call center schema design specifies the new tables and modifications to the existing tables, such as customer. The designers should also provide a reasonable specification for the ETL process. You need to drill down on those specifications to a finer detail, discussing what the designs mean within the context of modifications to a system in production. In other words, you need to think through, at a high level, how you're going to modify the existing ETL system to incorporate the new workload. You also need to consider whether you're going to alter the existing customer table or rebuild it. In either case, you must think about any implications on the SLA.

One of the most important issues to resolve during the planning phase is how to handle the modification of the customer dimension to track history. By far the easiest approach is to start tracking history now. All existing historical data gets associated with the customer's attributes as they are today. New facts get correctly associated with future changes in customer attributes. Often it's the only feasible approach because the history of customer attributes, address in our example, is simply unavailable. Note that even with this simple approach, you might need to modify the ETL process for retail sales so that you're propagating the correct customer key into the fact table. In practice, the retail sales ETL process likely picks up the most current customer key, but you'd be foolish to exclude verification of this point from your test plan.

A more challenging approach is to re-create history for a customer. You may be able to build a version of the customer dimension that includes the history of customer address changes. This is seldom easy, but may be possible. If it's possible, it's the job of the data warehouse team leader to present management with a cost benefit analysis of the effort. If you decide to take on this challenge, you have a second decision: whether or not to re-create history for the retail sales schema. The process of re-creating history in the fact table is conceptually simple because you know the sales transaction dates and the dates for which a customer's address is valid. However, performing this simple action requires updates on a significant number of fact table rows, which is an expensive operation. A second cost benefit analysis is required. And don't forget to develop a test plan to ensure you didn't mess things up!

Finally, your plan should discuss how to handle the proliferation of these changes to aggregate tables and OLAP cubes. If these structures are affected at all, they probably need to be rebuilt from scratch. Adjust your schedule accordingly, and don't forget your test plan.

Develop, Test, Deploy

The development of the new database elements and ETL processes is typically done against a small subset of data. This approach is only sensible. But developers need to remain constantly aware that they're adding new elements to an existing production system with potentially significant data volumes. A technique such as dropping and re-creating a table might work just fine in the development environment, but could be a complete disaster in the real world.

The test environment is the place to verify that the database can be upgraded, new data sources added, and new transformations processed without adversely affecting the existing operations. The first thing you need to do in the test environment is back up the entire system: data structures, data, and ETL processes. You need to test these main things: the new database structures, the ETL processes, and the process of migrating to the new structures and processes. Each test iteration should start from a clean system that hasn't had any of the migration changes applied to it (in other words, a system just restored from backup). Although early testing can be performed against a subset of data, your final set of tests should operate against a comprehensive environment, ideally an exact copy of the production system that you'll be modifying.

It's difficult to determine how to test the migration process. People often use this time as an opportunity to migrate the data warehouse to new hardware, which they've been testing as a shadow system. If you're running your data warehouse on commodity hardware, it's not terribly difficult to justify this approach. But if you have huge data volumes in production, you probably have no choice but to invest some serious planning and testing time to “doing it right.”

Some Final Thoughts

Much of the pain discussed in this article can be avoided if the initial design for retail sales thinks a few steps ahead to anticipate the need for address change tracking. One of the elements of art in data warehouse design is to think just broadly enough without being sucked into getting all requirements from all users. Realistically, it's a characteristic of a successful data warehouse to change over time, and the data warehouse team should be prepared to accommodate those changes.

In general, my recommendations are: Plan, plan, plan. Communicate. Develop. Test, test, test.

Sustaining for Ongoing Impact

In this final section, we focus on doing the right things to keep your DW/BI system on the right track. Since staying on course is directly related to establishing that path in the first place, you'll find quite a few pointers to earlier Reader articles.

We begin this section with a recommendation to conduct periodic checkups to verify that your DW/BI implementation is in good health. Subsequent articles address the sponsorship, business acceptance, architecture, and data “illnesses” typically uncovered during a health assessment. We finish with a responsibility you may not have planned for: preparing for the shut down of production applications and their associated data sources.

1 14.5 Data Warehouse Checkups

Margy Ross, Intelligent Enterprise, Jun 12, 2004

It's human nature to resist visiting a doctor for periodic checkups. Generally, we'd prefer to avoid being poked and prodded, having our vital signs taken, and then being told that we need to quit smoking, exercise more, or change our lifestyle habits in some fashion. However, most of us are mature enough to realize that these regular checkups are critical to monitor our health against conventional and personal norms.

Similarly, it's critical to conduct regular checkups on your DW/BI environment. It's less invasive to just keep doing what you've grown accustomed to in your DW/BI environment, but it pays to regularly check its weight and blood pressure, as well as the pulse of the business community.

Just like the assortment of health guides available in your doctor's office, we'll describe the most common disorders encountered when performing DW/BI checkups. For each malady, we'll then discuss the telltale symptoms to watch for, as well as prescribed treatment plans.

This article is pertinent to anyone with a maturing (dare we say “graying”) DW/BI system. Those of you just getting started should also watch for these warning signs to nip any disorder in the bud before it takes hold and spreads within your environment.

Business Sponsor Disorder

One of the most common, yet potentially fatal disorders involves the sponsorship of the DW/BI environment. A business sponsor disorder is often the key contributor to data warehouse stagnation.

Symptoms

Organizations are most vulnerable to this disorder when the original sponsor moves on either internally or externally. Even though someone will ultimately fill the job or assume the title, the new person likely isn't as zealous as the original sponsor. If the original sponsor left under somewhat negative circumstances, many of the assumptions concerning the data warehouse effort may be at risk, including tool selection, identity of trusted vendors, and even the chosen business process subject area. The political winds at the moment of such a transition can be especially turbulent.

Even if the sponsor hasn't changed jobs, he or she may mentally abdicate sponsorship duties. Newly formed data warehouse teams are especially susceptible. Once the team gets approval to proceed with the DW/BI initiative, it turns its complete attention to building the new environment as promised. In the meantime, another hot issue distracts the business sponsor (who potentially suffers from attention deficit disorder).

Another warning sign is if IT is the primary sponsor of the DW/BI program, establishing priorities and driving the development plan. Finally, if you find DW/BI funding suddenly coming under intense scrutiny, you're likely suffering from sponsorship disorder.

Treatment Plans

The first step to treat this disorder is to identify and recruit a business sponsor. An ideal business sponsor visualizes the potential impact of the DW/BI environment on the business, which empowers the sponsor with enthusiasm to ensure that the larger business community embraces the DW/BI deliverable. If the sponsor isn't engaged and passionate about the cause, then it's tough to convey that to the rank and file. Effective sponsors often face a compelling problem that they're trying to address. Good sponsors are able to leverage this compelling problem to provide the project with momentum by insisting the organization can't afford not to act.

We look for business sponsors who are influential within their organizations, both in terms of hierarchical and personal power. DW/BI sponsors need to be politically astute and understand the culture, players, and processes. Because neither the business nor IT communities can effectively construct the DW/BI world independently, business sponsors should be realistic and willing to partner with IT. A business sponsor should be a thoughtful observer of the IT development cycle, knowing when in that cycle to ask for new capabilities.

The most obvious way to find a business sponsor is to conduct a high level assessment of the business requirements. Likely sponsor candidates will rise to the top of the surface as a result of this process. Another approach is to conduct a demonstration proof of concept, presuming expectations can be realistically managed.

If no one emerges as a potential willing and able sponsor, then the project team should seriously reconsider moving ahead. You absolutely need someone high in the business to champion the cause. Otherwise, you'll suffer from chronic business sponsor disorder. The estimated lifespan of a DW/BI environment plummets without strong business sponsorship.

Your work isn't done once you've identified and recruited a single sponsor. Given the never-ending nature of the DW/BI program, sponsorship needs to be institutionalized with a steering committee or governance group of senior business and IT representatives. Clearly, you don't want to put all your sponsorship eggs in one basket.

One of our favorite tools for working with business sponsors is the prioritization quadrant, described in article 4.10, The Bottom-Up Misnomer. This technique is used in the early stages of a data warehouse to align business and IT priorities, resulting in a program roadmap for the enterprise. On an ongoing basis, perhaps every six months to a year, the DW/BI sponsorship or governance group should review progress to date and revisit the prioritization quadrant to queue up subsequent projects balancing business value and feasibility.

You need to establish a “care and feeding” program for the DW/BI sponsors. Business sponsors are highly experienced and respected businesspeople, however, they may not be highly experienced in the organizational culture change often required for an analytic initiative. They may need some coaching on their new roles and responsibilities. Take a look at article 3.11, Habits of Effective Sponsors, for more details.

Never take your sponsors for granted. It's certainly not safe to rest on your laurels. You need to constantly communicate, feeding constructive, realistic, and solution-oriented feedback to the sponsors, while listening to stay abreast of sponsors' hot buttons. Communication is also critical to continually build bridges with other business leaders in the organization. Lastly, you should actively convey what the DW/BI world has done for them lately. You can't afford to wait until someone's scrutinizing expenditures to inform them of your successes. As uncomfortable as it may seem, you need to market the DW/BI environment. Enthusiastic business users typically deliver the most effective commercials.

Data Disorder

Accessing good data is one of the two pillars of the data warehouse. (The other is addressing the right business problems.) The most serious and common data disorders are poor quality data, incomplete data, and late data.

Symptoms

One of the key indicators of a data disorder is the degree of data reconciliation happening across the organization because the data is inconsistent or not trusted. Data disorders are often blurred with business acceptance shortfalls when the real underlying issue is that the data is irrelevant or overly complex.

Treatment Plans

The initial treatment for data disorders requires drafting an enterprise data warehouse bus matrix. The matrix establishes a blueprint for enterprise integration by identifying the core business processes and common, conformed dimensions. After the matrix is developed, it should be communicated and “sold” up, down, and across the organization to establish enterprise buy-in. If you already have a slew of disconnected analytic data repositories, you can embellish the bus matrix by cataloging the “as is” environment prior to developing action plans for your longer term data strategy.

While the bus matrix identifies the links between core business process subject areas in the data warehouse, it also highlights opportunities for ETL processing. Like the overall technical architecture, the back room ETL architecture is often created implicitly rather than explicitly, evolving as data profiling, quality, and integration needs grow. You may need to rethink the staging and ETL architecture to ensure consistency and throughput at acceptable costs.

You should preface the DW/BI project with a comprehensive data profiling task to confirm that the data is what it's advertised to be. During the production phase, you must continuously monitor the data for quality glitches and omissions. Finally, you should carefully examine whether you need to go to a streaming real-time architecture to deliver the data to decision makers within their “sweet spot” time window for affecting the business.

Data disorders often result when data is irrelevant, incomprehensible, or otherwise difficult to use. Review your existing data schemas for potential improvements. We identified guidelines for reviewing presentation dimensional models in article 7.11, Fistful of Flaws.

Finally, if you've invested a lot of time and resources to develop an atomic, normalized data warehouse but the business users complain that it's too complicated and slow, you can leverage that existing investment by creating complementary dimensional models to address ease of use and query performance, while also boosting your chances of business acceptance.

Business Acceptance Disorder

Here's another critical disorder affecting data warehouse mortality rates. If the business community doesn't accept the DW/BI environment to support decision making processes, then you've failed. Sorry to be so blunt, but it's a harsh reality. The business must be engaged if you're to stand any chance of DW/BI acceptance. Unfortunately, business engagement is often outside our comfort zones; we may be unsure about techniques for ensuring their engagement, plus there are typically no incentives in place for mastering this domain.

Symptoms

There are some strong indications of business acceptance disorder. Are the business users simply not using the data warehouse like you expected they would? Do the number of BI tool licenses greatly exceed the number of active users? Do the number of trained users greatly exceed the number of active users? Are the prime targeted beneficiaries of the DW/BI environment turning their attention to a different analytic platform, independent of the data warehouse? Do the business users make requests like “just give me a report with these three numbers on it” because they're loading the report into Excel where they're building their own personal data warehouse? Does the business community perceive a legacy of disappointment when it comes to IT's ability to address their requirements? Did the DW/BI project team focus on data and technology, presuming they understand the business's requirements better than the business does?

Treatment Plans

Your mission is to engage, or reengage, the business. Talking to users about their requirements is an obvious place to start. The DW/BI environment is supposed to support and turbocharge their decision making. Given this mission, distributing surveys or reviewing entity-relationship diagrams are ineffective tools for gathering business requirements. Put yourself in their shoes to understand how they currently make decisions and how they hope to make decisions in the future. Obviously, you need to have the right attitude, listen intently, and strive to capture their domain expertise.

It's important that you engage business folks across a vertical span of the organization. It's not enough to merely speak with pseudo IT power analysts who can make data jump through hoops. We need to talk to their peers who aren't so empowered, plus speak with middle and upper management to better understand where the organization is going. If you spend all your time in the trenches, you're vulnerable to being shortsighted by focusing solely on today's problems while ignoring the bigger issues looming in the future. It's highly beneficial to have relationships with all levels of the business organization, including executives, middle management, and individual contributors.

Of course, you're more likely to successfully engage the business when you have a strong business sponsor with a powerful ability to influence the organization. A strong, committed business sponsor can significantly affect the organization's culture. Conversely, if you suffer from a sponsorship disorder, it's even harder to obtain business acceptance. These two disorders often go hand in hand.

As previously discussed, one size doesn't fit all when it comes to analytic capabilities. You need to acknowledge the range of usage requirements and institutionalize a strategy to address the spectrum, as discussed in article 13.2, Beyond Paving the Cow Paths.

Similar to our discussion about business sponsor care and feeding, you need to establish a comparable program for the rest of the business community. Care and feeding commonly occurs with the initial deployment, but then we often quickly turn our attention to the next project iteration. You need to proactively conduct ongoing checkpoint reviews to remain engaged with the business. In addition, you should help the business users understand their shared responsibility for a healthy DW/BI program.

Education is a key component of deployment, but it isn't a one-time event. You need to consider ongoing needs for tool, data, and analysis education. We've worked with some organizations that include DW/BI training as part of their new hire orientation because information is a fundamental part of their culture. Not surprisingly, the DW/BI environment is broadly accepted in these companies; it's part of the way they do business.

Finally, as we described with the sponsorship disorder, communication is critical. You can't rely solely on traditional project documentation tools to communicate with all your constituencies. You need to concentrate on what's in it for them, marketing successes while managing expectations.

Infrastructure Disorder

Contrary to popular opinion, infrastructure disorders are seldom fatal. There's often room for improvement, but it's usually an elective procedure. Despite our personal interests in this disorder, it usually doesn't warrant the attention due the others.

Symptoms

Are the DW/BI systems slow or is the data late? Is the DW/BI environment commonly described as a bundle of technical bells and whistles? Are there tool overlaps and/or voids? What about performance concerns? Performance covers a gamut of potential underlying problems: ETL processing time to get the data loaded, query result time lags, and the DW/BI development cycle time to deliver new functionality.

Treatment Plans

Every DW/BI environment is based on an architectural foundation; however, it may be time to revisit your overall architecture plan. The question is whether your plan was explicitly developed, or whether it just implicitly occurred. A well thought out plan facilitates communication, minimizes surprises, and coordinates efforts.

Revisiting your technical architecture doesn't mean going out and buying all the latest, greatest technology. You need to understand the business's needs and determine the associated implications on the technical architecture in terms of the required ETL services, BI access/analysis services, infrastructure, and metadata. The drive toward more real-time data warehousing is a prime example of the translation from business needs into architectural requirements. Some organizations have made poor technology choices in the past. It takes courage to unload that baggage to enhance the DW/BI environment going forward.

Cultural/Political Disorder

Unfortunately, DW/BI environments aren't immune to cultural or political disorders, and there's no vaccine in development on the research horizon.

Symptoms

Symptoms of this disorder are fuzzier to articulate, especially because they typically transcend more than the DW/BI environment. Organizations with cultural and political disorders may be stymied by conflicting priorities of “doing it fast” versus “doing it right.” Similarly, they often struggle to reach consensus on tough issues, such as data standardization and process changes. Be especially watchful when it comes time to reach agreement on the rollout of conformed dimensions since that is when talking ends and action begins. Finally, more specifically related to DW/BI, many organizational cultures aren't poised to embrace analytic decision making, especially when decisions have traditionally been based on gut feelings or intuition. Do the business users currently manage by the numbers? There's often a lack of recognition and/or willingness to champion a culture shift to more fact-based decision making.

Treatment Plans

When dealing with cultural and political disorders, you can't just duck them, much as you would like. You need to be courageous, while understanding that these disorders are difficult to overcome with trench warfare. Now is the time to call in your support group: IT management, business sponsors, and the business community. If the support group doesn't recognize the need and assume accountability for treating these disorders, then the DW/BI team is in for a long, uphill struggle. Senior business and IT management must accept its fiduciary responsibility for handling information and analytics as corporate assets. Finally, actions speak louder than words. The organization will easily see through a veil of verbal commitment if management doesn't exhibit reinforcing behaviors.

Early Detection

With many maladies, early detection is essential to mounting a strong defense. Similarly, proactively monitoring your data warehouse and business intelligence environment is the best method of ensuring its long term health. It's tough to prescribe a remedy if you don't know what you're suffering from. As a student commented recently, thinking about common disorders and alternative treatment plans is a “shot in the arm” for anyone who's trying to rescue a failing data warehousing project. The metaphor lives on.

Finally, remember there's nothing wrong with having a checkup and learning that you're in perfect health. In fact, that's the optimal outcome!

14.6 Boosting Business Acceptance

Bob Becker, Intelligent Enterprise, Aug 7, 2004

Article 14.5, Data Warehouse Checkups, discussed the importance of regularly casting a critical eye over your DW/BI program. Checkups identify early warning signs and symptoms so appropriate treatment can occur before more serious consequences are encountered down the road.

One of the more troubling DW/BI maladies is the business acceptance disorder. In layperson's terms, the business community isn't using the DW/BI environment; it's just not a critical component of the business decision making process. Frankly, this is a frightening diagnosis for project teams. It's impossible to declare DW/BI success if no one in the business has embraced the results of your hard work and best intentions.

Business acceptance shortfalls must be rectified quickly once the symptoms are recognized to get the DW/BI effort back on track. The Kimball Group has talked and written extensively in the Toolkit books about the importance of embracing business users early in a new DW/BI initiative to understand their requirements and garner their buy-in. We use a similar approach for reengaging the business community. This article describes the fundamental techniques so you can comfortably and confidently get back in sync with the business to ensure ongoing involvement and acceptance.

DW/BI Business Realignment

Viewing the DW/BI project through the business users' eyes is an effective method to realign with the user community. In cooperation with the business sponsor, DW/BI team representatives should talk with the business community about the ability of the environment to effectively support their needs. Results of this process are then analyzed and presented back to the business with appropriate recommendations.

The most important aspect of the realignment process is meeting with the business community to solicit their feedback. We talk to them about what they do, why they do it, how they make decisions, and how they hope to make decisions in the future. Along the way, we also need to understand how the current DW/BI efforts support this process as well as any issues and concerns regarding the DW/BI environment. Like organizational therapy, we're trying to detect the issues and opportunities.

Choose the Forum

Before meeting with the business community, determine the most appropriate forum for a productive session. There are two primary techniques for gathering feedback: interviews and facilitated sessions. For a realignment project, interviews are preferable to facilitated sessions. Because lack of business acceptance is suspected, it's reasonable to expect some negative reactions to the existing environment. You should avoid facilitated group sessions, which may disintegrate into finger pointing, blame casting complaint sessions counterproductive to your mission of reinvigorating business acceptance. Besides, interviews encourage a lot of individual participation and are easier to schedule.

Surveys aren't a reasonable tool for gathering realignment feedback. Business users are unlikely to feel their issues have really been heard through a survey. Most won't bother to respond. Surveys are flat and two dimensional; those who do respond will only answer the questions you've asked in advance. There's no option to probe more deeply like you can when you're face to face. A key outcome of the realignment process is to create a bond between users and the DW/BI initiative. This outcome just doesn't happen with surveys.

Identify and Prepare the Interview Team

It's important to identify and prepare the involved project team members, especially as some of the interviews could become contentious. The lead interviewer must ask great open-ended questions, but also needs to be calm and mature, capable of receiving negative feedback without taking it personally and becoming defensive or combative. The interview scribe needs to take copious notes, pages of them from each session. A tape recorder isn't appropriate for the realignment effort because it may cause interviewees to hold back on key organizational issues. Although we often suggest inviting one or two additional project members as observers in an initial requirements gathering effort, this practice is less desirable in a realignment project because you'll want the interviewees to be as open and honest as possible.

Before sitting down with the participants, make sure you're approaching the sessions with the right mindset. Don't presume that you already know it all; if done correctly, you'll definitely learn during these interviews. Prepare yourself to listen effectively without becoming defensive. These sessions are the business community's opportunity to share their perspective of the DW/BI project. They aren't intended for you to try to explain how or why the situation developed.

Select, Schedule, and Prepare Business Representatives

The businesspeople involved should represent the horizontal breadth of the organization. Obviously, you'll schedule individuals from groups currently served (or meant to be served) by the DW/BI environment. In addition, you should include groups that are potential DW/BI candidates. You want to uncover any issues that may be constraining the DW/BI project's ability to serve these needs.

You also want to be sure to cover the organization vertically. Project teams naturally gravitate toward the superpower business analysts who are the most frequent and capable DW/BI users. While their insight is obviously valuable and important, don't ignore senior executives and middle management. Otherwise, you're vulnerable to being overly focused on the tactical here and now but losing sight of the real reasons for flagging business acceptance.

Scheduling the business representatives can be an onerous task. Be especially nice to any assistants as calendars are juggled. We prefer to meet with executives on their own, whereas we can meet with a homogeneous group of two to three people for those lower on the organization chart. We allow one hour for individual meetings and one and a half hours for the small groups. The scheduler needs to allow a half hour between meetings for debriefing and other necessities. Interviewing is extremely taxing because you must be completely focused for the session's duration. Consequently, we only schedule three to four sessions in a day because our brains turn mushy after that.

When it comes to preparing the interviewees, the optimal approach is to conduct a launch meeting with the participants. Business sponsors play critical roles, stressing their commitment and the importance of everyone's participation. The launch meeting disseminates a consistent message about the realignment effort. It also generates a sense of the business's project ownership. Alternately, if the launch meeting is a logistical nightmare, sponsors should communicate the same messages via launch memos.

Conduct the Interviews

It's time to sit down face to face to gather feedback. Responsibility for introducing the interview should be established prior to gathering in a conference room. The designated kickoff person should script the primary points to be conveyed in the first couple of minutes when the meeting tone is established. This introduction should convey a crisp, business-centric message focused on the realignment project and interview objectives. Don't ramble on about the hardware, software, and other technical jargon.

The goal of the interview is to get business users to talk about what they do and why they do it. Although in the long run you want to understand how well the existing DW/BI environment aligns with decision making processes, you don't want to be singularly focused on the DW/BI project's current state too early in the interview. You're most interested in how the organization uses information to make decisions so that you can align your efforts.

A simple, nonthreatening place to begin is to ask about job responsibilities and organizational fit. This is a lob ball that interviewees respond to easily. From there, we typically ask about their key performance metrics and how they use information in support of decision making. Ultimately, we ask about their experience with the DW/BI project and its ability to support their requirements. If the interviewee is more analytic and hands on, we ask about the types of analyses currently performed, how easily they're developed, and how well they deliver. When meeting with business executives, ask them about their vision for better leveraging information in the organization. You're seeking opportunities to align future data warehouse deliverables with business demand.

As the interview comes to a conclusion, we ask interviewees about their success criteria for the DW/BI environment. Of course, each criterion should be measurable. Easy to use and fast mean something different to everyone, so you need to get the interviewees to articulate specifics. At this point in the interview, we make a broad disclaimer. The interviewees must understand that just because an opportunity was discussed doesn't guarantee that it will be resolved immediately. You need to take advantage of this opportunity to manage expectations. Finally, thank interviewees for their insights and let them know what's happening next.

Document, Prioritize, and Reach Consensus

Now it's time to write down what you heard. While documentation is everyone's least favorite activity, it's critical for both user validation and project team reference materials.

Two levels of documentation typically result from the interview process. The first is to write up each individual interview. This activity can be quite time consuming because the write-up shouldn't be merely a stream of consciousness transcript, but should make sense to someone who wasn't in the session. The second level is a consolidated findings document. We typically begin with an executive summary, followed by a project overview that discusses the process used and participants involved. The bulk of the report centers on the findings, including specific opportunities for improving, enhancing, and expanding the existing DW/BI environment to better address business needs and expectations.

The realignment findings document serves as the basis for presentations back to senior management and other business representatives who participated. Inevitably, you've uncovered more opportunities than can be tackled immediately, so you need to develop consensus regarding priorities. Prioritization of efforts is an important step in leveraging and fostering an improved partnership to ensure the DW/BI effort aligns with the business. A highly effective tool for reaching agreement on a DW/BI roadmap and action plan is the prioritization quadrant, discussed in article 4.10, The Bottom-Up Misnomer.

At this point, the DW/BI team has a solid understanding of what needs to be accomplished to better support the business community's requirements and expectations. Delivering on the opportunities identified during the realignment process will establish an improved DW/BI environment that's embraced and accepted across the organization.

14.7 Educate Management to Sustain DW/BI Success

Warren Thornthwaite, Intelligent Enterprise, Aug 27, 2007

Most large organizations have fairly mature DW/BI systems in place, and many of these have met with some measure of success. Unfortunately, in this “what have you done for me lately” world, success is not a single event you can gloat about as you kick back with your feet on the desk. Continued success is a constant process of building and maintaining a solid understanding of the value and purpose of the DW/BI system across the organization. We call this education, but many of the techniques involve marketing and organizational strategies. Call it what you will, you must actively and constantly promote the DW/BI system.

First, you need to know who your stakeholders are and make sure you have standard communications tools in place, like status notes, newsletters, and quantitative usage reports. There are also a few qualitative and organizational tools you can use to educate management about the value and purpose of the DW/BI system.

Gathering Evidence

While usage statistics are interesting, they show only activity, not business value. Simple query counts tell you nothing about the content or business impact of those queries. Unfortunately, there's no automated way of capturing the value of each analysis from the DW/BI system. You still have to get this information the old fashioned way, by talking to people. Someone on the DW/BI system team has to go out into the user community on a regular basis and ask people to describe what they are doing, assess the business impact it has had, and document it.

Most of the time, the impact of any given analysis isn't all that stunning. People do useful things that make a big difference in their work, but it's not a multi-million dollar hit. Every so often, you will find an analysis or operational BI application that has had a significant impact. For example, the analyst may have identified a pattern of calls in the customer care data that led to a simple change in the documentation and reduced the call volume by 13 percent (at $6 per call, that's over $140,000 per year for a company that takes 500 calls per day). Or they may have analyzed the donor database in a small nonprofit organization and identified donors who had dropped out. This led to a special program to reconnect with these people that yielded a 22 percent response rate and close to $200,000. Or the operational BI application may offer ring tone recommendations on a web site based on customer purchase history. Each ring tone may fetch only $1, but a 30 percent increase in ring tone downloads could add up to real money. You get the idea.

Educating the Business: The User Forum

Finding high impact examples requires a bit of work. One effective technique the Kimball Group has used to identify and leverage qualitative examples of value is called a user forum. The user forum is a DW/BI event designed for the business community. Your main business sponsor should kick off this 90 minute meeting with a short speech about how important the DW/BI system is to the organization's success. The first agenda item is a brief presentation from the team about the recent accomplishments, current state, and short term plans of the DW/BI system. The bulk of the meeting is dedicated to two presentations from business analysts who used the BI system to generate significant value for the organization. They talk about what they did, how they did it, and what kind of impact it had.

Senior managers like these events because they see the impact. Often the head of one department will see what another department has done and realize his group is missing an opportunity. Middle management and analysts like the presentations because they include enough detail so people can see exactly how the analysis was accomplished. They learn new techniques and approaches to the analytic process. The three examples of business value described in the preceding section would be great feature presentations at a user forum.

A good meeting doesn't happen by accident. Find good presentation candidates with high business value by canvassing users on a regular basis. Once you find a good example, work with the user to create a clear, compelling presentation with lots of screen captures and a summary page that shows the dollar impact of the analysis. Rehearse the presentation with them, especially if they are not experienced presenters. This helps you, and them, get the timing down so your audience doesn't miss the punch line because the meeting went too long. Email a reminder a day or two ahead of time, and call everyone you'd like to be there to make sure they are going to make it to the meeting. If key folks, like the CEO or VP of Marketing, can't make it, consider rescheduling rather than have them miss out. If they are already on your side, it's good to have the show of support; if they are not converts yet, they could learn something by being at the meeting.

Schedule user forum meetings on a regular basis, about every six months or so. Don't be too proud to employ blatant marketing techniques to promote the meeting. The basics almost go without saying: food and drink are a must. Consider offering marketing swag as prizes. Since most BI teams are friendly with the marketing group, see if they'll let you raid their goodies closet.

It's a great idea to keep the presentations on file. After a year or two, you will have a library of powerful business value examples. Put a link to them on your BI portal. Print them out and make a welcome packet you can present to every new executive.

Educating Senior Staff

Your top educational priority in the long term should be to continuously and consistently inform senior management about what the DW/BI system is, why it's important, how it should be used, and what it takes to make it happen. The user forum helps achieve this objective, but the greater your access to senior management, the easier this education process will be.

Ideally, the head of the DW/BI system is part of senior staff and participates in their planning meetings. If not, try to get a regular slot on their meeting schedule to present success stories and plans and to hear about potential changes in business priorities.

Often, senior management will want to explore an idea to see if it's viable before launching any major new initiatives. Having a direct line to the DW/BI team can help senior management quickly triage ideas that should be abandoned and those that should be developed further. Once an idea begins to gain traction, the DW/BI team should make sure its development is accompanied by appropriate measurement and analytical systems. All too often, we've seen new initiatives taken on by senior management with no means to measure impact or value. If the data is not collected, you can't analyze it.

Bottom line: However you make it happen, you need to make sure someone on the DW/BI team is involved with senior management and understands where the business is headed so you can be prepared to support it.

Working with Steering Committees

If it's not politically possible for the DW/BI team leader to be part of senior staff, another way to get the information you need is to establish an ongoing steering committee for the DW/BI system made up of senior-level business representatives. If you don't have a steering committee, try to recruit people who you know will be able to work together, give you the information you need, and wield some influence in the organization. You might call this group the Business Intelligence Directorate (BID), or some other important sounding name with a nice acronym. It may seem trivial, but naming is a big part of the marketing process.

You may also have a different kind of business user steering committee made up of analysts and power users who help prioritize lower level tasks and identify technical opportunities for the BI system. You might call this the BI Technical Experts (BITE) group.

Conclusion

You may feel that because you've done a good job, you shouldn't have to continually market the DW/BI system, or educate the business community. Unfortunately, that's not the case. You need to continually gather concrete evidence of success and use that to educate senior management. You also need to be informed of and have some influence over the decision making process at the senior staff level, either through direct participation or via a steering committee. This may sound like a burden, but one positive result is that as senior management understands the business value of the DW/BI system, they no longer question your budget.

14.8 Getting Your Data Warehouse Back on Track

Margy Ross and Bob Becker, Design Tip #7, Apr 30, 2000

During the past year, we've repeatedly observed a pattern with maturing data warehouses. Despite significant effort and investment, some data warehouses have fallen off course. Project teams, or their user communities, are dissatisfied with the warehouse deliverables. The data's too confusing, it's not consistent, queries are too slow, and the list goes on. Teams have devoured the data warehousing best sellers and periodicals, but are still unsure how to right the situation, short of jumping ship and finding new employment.

If this situation sounds familiar, take the following self-check test to determine if the four leading culprits are undermining your data warehouse. Consider each question carefully to honestly critique your warehouse situation. In terms of corrective action, we recommend tackling these fundamental concerns in sequential order, if possible.

  1. Have you proactively gathered requirements from the business users for each iteration of the data warehouse development and aligned the implementation effort with their top priorities?

    This is the most prevalent problem for aging data warehouses. Somewhere along the line, perhaps while overly focused on data or technology, the project lost sight of the real goal to serve the information needs of business users. As a project team, you must always focus on the users' gain. If the team's activities don't provide benefit to the business users, the data warehouse will continue to drift. If you're not actively engaged in implementing solutions to support users' key business requirements and priorities, why not? Revisit your plans to determine, and then focus on delivering to, the users' most critical needs.

  2. Have you developed an enterprise data warehouse bus matrix?

    The matrix is one of the data warehouse team's most powerful tools. See article 5.5, The Matrix. Use it to clarify your thinking, communicate critical points of conformance, establish the overall data integration roadmap, and assess your current progress against the long term plan.

  3. Is management committed to using standardized conformed dimensions?

    Conformed dimensions are absolutely critical to the viability of a data warehouse. We find many warehouse teams are reluctant to take on the socio-political challenges of defining conformed dimensions. In all honesty, it's extremely difficult for a data warehouse team to establish and develop conformed dimensions on its own. Yet the team can't ignore the issue and hope it will resolve itself. You'll need management support for conformed dimensions to help navigate the organizational difficulties inherent in the effort.

  4. Have you provided atomic data in dimensional models to users?

    Data shortcomings, whether it's the wrong data, inappropriately structured, or prematurely summarized, are often at the root of data warehouse course adjustments. Focusing on business requirements will help determine the right data; then the key is to deliver the most atomic data dimensionally. Unfortunately, it's tough to gracefully migrate from data chaos to this nirvana. In most cases, it's best to bite the bullet and redeploy. Teams sometimes resort to the seemingly less drastic approach of sourcing from the current quagmire; however, the costs are inevitably higher in the long run. Often the granularity of the existing data precludes this alternative due to premature summarization.

In summary, if your data warehouse has fallen off course, it won't magically right itself. You'll need to revisit the basic tenets of data warehousing: Listen to users to determine your target destination, get a map, establish a route, and then follow the rules of the road to get your data warehouse back on track.

14.9 Upgrading Your BI Architecture

Joy Mundy, Design Tip #104, Aug 7, 2008

Article 13.1, The Promise of Decision Support, described the typical lifecycle of a business analysis:

  1. Publish standard reporting and scorecards. How's my business doing?
  2. Identify exceptions. What's unusually good or bad?
  3. Determine causal factors. Why did something go well or poorly?
  4. Model predictive or what-if analysis. How will business look next year?
  5. Track actions. What's the impact of the decisions that were made?

What do you do if you're stuck at step 1? What if you have an infrastructure that supports basic reporting, but is the wrong architecture to enable complex analytics or business user self-service? How do you get to where you want to go? In some ways it's easier to start from a blank slate and do it right the first time; it's easy to be a hero when you're starting from zero. But large companies, and a growing number of medium and even small companies, already have some kind of DW/BI system in place. There are additional challenges in moving to a new architecture at the same time you have to maintain the existing system and users.

There are three common unsuccessful DW/BI architectures:

  • Normalized data warehouse with no user-focused delivery layer. The organization has invested in a data warehouse architecture, but stopped short of the business users. The data warehouse is normalized, which means it may be simple to load and maintain, but not easy to query. Reports are written directly on the normalized structures, and often require very complex queries and stored procedures. In most cases, only a professional IT team can write reports.
  • Normalized data warehouse with mart proliferation. A common approach to solving the problem of data model complexity is to spin off data marts to solve specific business problems. Usually these marts are dimensional (or at least can pass as dimensional in the dark with your glasses off). Unfortunately, they are limited in scope, contain only summary data, and are un-architected. A new business problem requires a new mart. Users' ad hoc access is limited to the scenarios that have been cooked into the standalone marts.
  • Mart proliferation directly from transaction systems. The least effective architecture is to build standalone data marts directly from OLTP systems, without an intermediate DW layer. Each mart has to develop complex ETL processes. Often, we see marts chained together as one mart feeds the next.

In any case, the appropriate solution is to build a conformed, dimensional data warehouse delivery area.

If you already have a normalized enterprise data warehouse, analyze the gap between the business requirements and the existing data warehouse's contents. You might be able to build relatively simple ETL processes to populate the dimensional data warehouse from the normalized one. For any new business processes and data, determine whether the normalized DW provides value in your environment. If so, continue to integrate and store data there, then dimensionalize and store it again in the dimensional structure. Alternatively, you may find that it makes more sense to integrate and dimensionalize in one ETL process, and phase out the normalized data warehouse. Once the data is in the conformed dimensional model, you'll find that business users have much greater success self-servicing and developing ad hoc queries. Some of those ad hoc queries will push up into exception, causal, and even predictive analysis, and will evolve into BI applications for the broader audience.

If you don't have a normalized data warehouse in place, you probably won't build one. This scenario is more like the “starting from scratch” approach using the Kimball Lifecycle method. You'll need to gather business requirements, design the dimensional model, and develop the ETL logic for the enterprise dimensional data warehouse.

Arguably the biggest challenge in building an upgraded architecture is that your users' expectations are higher. You'll need to keep the existing environment in place and provide modest improvements while the new system is being developed. If you're starting from scratch, you can make users happy by rolling out the new system a little bit at a time. With a BI upgrade or replacement project, your phase 1 scope is likely going to have to be bigger than we normally recommend to make a splash.

You need to plan for people and resources to maintain the existing environment as well as to perform the new development. We recommend that you devote a team to the new development; if the same people are trying to do the old and the new, they'll find their energies sucked into the constant operational demands of the user community. The entire group will have to expand, and the old team and new team both need business expertise and technical skills.

Once you roll out a core set of data in the upgraded environment, there are two paths you can take. You can go deeper into the initial set of data by building analytic applications that go beyond just publishing basic reports. Or, you can bring in data from additional business processes. With enough resources, you can do both at the same time.

1 14.10 Four Fixes for Legacy Data Warehouses

Margy Ross, Intelligent Enterprise, Oct 1, 2006

Few designers have the luxury of working with a blank slate when it comes to the development of their DW/BI environment anymore. Instead, many of us deal with the decisions, and potentially the sins, of our predecessors. Your DW/BI environment would likely look very different if you were to build it from scratch, but a complete toss-and-rebuild is seldom a viable alternative. More often, DW/BI professionals are tasked with making evolutionary upgrades and improvements to minimize cost and upheaval of the current analytic environment. The following four upgrades can breathe new life into legacy data warehouses.

Conform the Nonconformed Dimensions

Master conformed dimensions contain the descriptive attributes and corresponding names, meanings, and values that have been agreed to across the enterprise. Using conformed dimensions ensures that the data warehouse is delivering consistently defined attributes for labeling, grouping, filtering, and integrating data from multiple business processes.

Unfortunately, many data warehouses and marts were developed without regard for this critical master data. Standalone data stores with independently defined dimensions are often constructed because it's the path of least resistance when deadlines loom. Rather than attempt to reach consensus on common reference data, isolated teams believe it's quicker and easier to just build autonomous dimensions. This approach may let these teams declare victory, but it doesn't support the business' desire for integration and consistency.

Some organizations wind up with independent data stores because developers purposely focused on delivering a departmental solution, likely due to the funding available. Without the vision and acknowledged need for an enterprise perspective, teams are often chartered to build with blinders on to meet a limited set of goals.

So what do you do if you're confronted with an environment that's been built without a foundation of common conformed dimensions? Can these stovepipes be rescued? In spite of the vendor hype, there's no magic elixir that miraculously delivers master dimensions. Technology can facilitate and enable data integration, but there's no silver bullet. The first step toward integration nirvana is to assess the state of the data, as well as requirements, expectations, and buy-in from the business. You can self-diagnose the issues related to nonconforming dimensions, but keep in mind that you're likely to face a long, uphill internal struggle and resistance to change if the business community doesn't perceive the need or incremental value in the project.

As we described in article 5.14, Data Stewardship 101: The First Step to Quality and Consistency, one of the most crucial steps in conforming nonconformed dimensions is to organize the appropriate resources to tackle this vexing problem. Data stewards must be identified and assigned responsibility and authority to determine common dimension attributes, define domain values and transformation business rules, and establish ongoing processes to ensure data quality. Obviously, that's no small feat, so it's critical to identify the right leader. Ideally, you want someone from the business community who is respected by senior management and who has knowledge and skills to achieve organizational consensus. Navigating the unavoidable cross-functional challenges requires experience, widespread respect, political acumen, and strong communication skills.

Not everyone is cut out to be a data steward. It's feasible for folks on the data warehouse team to serve as stewards, but they need to demonstrate all the traits and characteristics just described. Most important, they need the support of business management and the authority to push cross-enterprise agreement and adoption, even when unpopular compromise is required. Without this power, stewards face the prospect of endless tire spinning as they try to rationalize diverse perspectives.

Once the data stewards produce the specifications for a conformed master dimension, the skilled ETL staff builds the master dimension. Depending on the existence and/or quality of reference data in the operational source systems, this may require intricate record matching and deduplication. When merging multiple source systems, clearly defined rules of survivorship are needed to identify which data source takes precedence for each attribute.

With master dimensions built, it's then time to retrofit the existing data warehouse subject areas with standardized data. New surrogate key mapping tables for each dimension are used to recast existing fact table rows. In addition, aggregate summary tables and cubes will likely need to be reconstructed. While the implications for the ETL system are inevitably significant, hopefully the impact on the business intelligence layer of these underlying physical table changes can be minimized with an abstraction layer using views, synonyms, or your BI tool's metadata, depending on your platforms.

Create Surrogate Keys

Another data warehousing best practice is to create surrogate keys, typically a meaningless simple integer, for the primary key in each dimension table. The associated fact table rows use this same surrogate as a foreign key reference to the dimension tables.

Establishing, managing, and using surrogate keys may initially feel like an unnecessary burden on the ETL system, so many data warehouses have been constructed based on the operational natural keys, sometimes referred to as smart keys because of their embedded meaning, rather than using surrogates. At first blush, these natural keys may not present any obvious problems. But as the environment matures, teams often wish things had been done differently when the following situations arise:

  • The natural keys in the operational system get recycled after a product has been discontinued or an account closed for more than a specified length of time. Two years of dormancy may seem like a lifetime to an operational system, but relying on reassigned natural keys can wreak havoc in the data warehouse where data is retained for extended periods.
  • The business decides it's important to track dimension attribute changes after all. While this need may not have been envisioned up front, as the business develops expertise with the data, team members often want to see the impact when descriptive dimension attributes change. Naturally gravitating to the least onerous route, they may have developed the initial data warehouse with the premise that dimension tables would reflect the most current attribute values, overwriting any previous descriptors when they change using the SCD type 1 technique. But the rules may now be maturing, requiring the insertion of new rows into the dimension table to capture new profiles via SCD type 2 methods. Relying on the natural key as the primary key of the dimension table obviously doesn't allow for multiple profile versions, while using a concatenated key based on the natural key and effective dates has a negative impact on both query performance and usability.
  • Performance has been negatively impacted by an inefficient natural key. In contrast to a tight integer, natural keys are often bulky alphanumeric fields that result in suboptimal dimension/fact table join performance and unnecessarily large indexes.
  • You must create conformed dimensions to integrate reference data from multiple sources, each with its own unique natural key. You may need a default dimension primary key to represent the condition when a dimension value is unknown or not applicable to a given measurement event.

Each of these situations can be addressed by using surrogate keys as the primary keys for the dimension tables. So how do you implement surrogates when you're already working with a system that was built without them? In the simplest scenario, you would add the sequential surrogate key to the dimension table, leaving the existing natural key intact as an attribute, and recast the fact rows to reference the new surrogate key values. Depending on your BI tool, you may need to update the tool's metadata to reflect the change in join fields. If you need to support type 2 attribute change tracking, additional work would be required to source the historical attribute profiles and then repopulate the fact table with the surrogate key values that were valid and in effect when the fact row occurred.

Deliver the Details

Some people believe dimensional models are only appropriate for summarized information. They maintain that dimensional structures are intended for managerial, strategic analysis and therefore should be populated with summarized data, not operational detail. The Kimball Group vehemently disagrees; in our view, dimensional models should be populated with the most detailed, atomic data captured by the source systems so business users can ask the most detailed, precise questions possible. Even if users don't care about the particulars of a single transaction or subtransaction, their question of the moment may require rolling up or drilling down in these details in unpredictable ways. Of course, database administrators may opt to presummarize information to avoid on the fly summarization in every case, but these aggregate summaries are performance-tuning complements to the atomic level, not replacements.

Restricting your dimensional models to summarized information imposes serious limitations. Summary data naturally presupposes the typical business questions so when business requirements change, as they inevitably will, both the data model and ETL system must change to accommodate new data. Summary data alone also limits query flexibility. Users run into dead ends when the presummarized data can't support an unanticipated inquiry. While you can roll up detailed data in unpredictable ways, the converse is not true; you can't magically explode summary data into its underlying components. Delivering dimensional models populated with detailed data ensures maximum flexibility and extensibility.

So what do you do if you've inherited a data warehouse filled with preaggregated information, but the details are missing in action? The solution is straightforward: You need to source and populate the bedrock atomic detail. Because more detailed data is naturally more dimensional, this will almost inevitably require that new dimension tables be constructed as well.

As you're delivering the details, don't be lulled into thinking that summary data should be dimensionalized but that atomic details are better handled in a normalized schema. Business users need the ability to seamlessly and arbitrarily traverse up, down, and across both the detailed and summary data in a single interface. While normalization may save a few bytes of storage space, the resulting complexity creates navigational challenges and typically slower performance for BI reports and queries.

Reduce Redundancies

Many organizations take a piecemeal approach to their data warehouse design and deployment, so it's common for the same performance metrics to reside in numerous analytic environments, often segregated by business department or function. The multiple, uncoordinated extracts from the same operational source systems required to populate these redundant data stores are inefficient and wasteful. Variations of similar, but different, information result from inconsistent business rules and naming conventions, causing unnecessary confusion and requiring reconciliation throughout the enterprise. Obviously, conflicting databases that perpetuate incompatible views of the organization are distracting resource drains.

Take a more enterprise-centric approach, storing core performance metrics once to support the analytic needs of multiple departments or groups. The enterprise framework is defined and communicated via the data warehouse bus matrix. The matrix rows represent the business events or processes of the organization, while the columns reflect the common, conformed dimensions. The bus matrix provides the macro point of view for architecting the data warehouse environment, regardless of database or technology preferences.

But what do you do if you've discovered that your organization's key performance metrics and indicators are currently available in many different analytic environments? The first step is to assess the damage. You can create a detailed implementation bus matrix, described in article 5.6, The Matrix: Revisited, to gather information and document your current state. With these details in hand, you're ready to help senior executives understand the quagmire resulting from uncontrolled, standalone development. Because they're often the ones demanding more information (and by the way, they want it delivered yesterday), it's important that they comprehend the consequences of piecemeal development, which can significantly hinder the organization's decision making capabilities.

If the business appreciates the inefficiencies and obstacles of the current environment, they are much more likely to support a migration strategy to reduce the unnecessary redundancies. Unfortunately, this rationalization often has serious ramifications on the BI application layer when the underlying data stores are removed or consolidated.

Face the Realities

We've described four of the most common data fixes for more mature warehouses. It's worth noting that regardless of the opportunities for improvement with your existing environment, it's important to evaluate the costs versus benefits of taking any corrective action. It's similar to the decision process when confronted with maintenance of an aging automobile; sometimes it makes sense to spend the money, but other times you may opt to merely live with the dents or dump the heap of junk altogether.

Keep your eyes open for occasions when the impact of the corrective action is either less noticeable or less painful. For example, if your organization is implementing a new operational source system or migrating to a new ETL or BI tool platform, the upheaval with your existing transformation or analytic processes presents an opportunity for other corrections. Using the automobile maintenance analogy, if your car is already in the shop and the mechanic has lifted the hood to change the oil, he might as well check the windshield wiper fluid while he's in there.

14.11 A Data Warehousing Fitness Program for Lean Times

Bob Becker and Joy Mundy, Intelligent Enterprise, Mar 16, 2009

It's no secret that the U.S. and global economies are facing difficult times. If the economic pundits are correct, we are now working through the most challenging economic decline of most of our lifetimes.

Many organizations have already made significant reductions in staffing and spending. The DW/BI sector seems to be faring somewhat better than others; in bad times as in good times, organizations desire better visibility into their business and improved decision making capabilities. Even so, many DW/BI teams are facing staff reductions or at least hiring freezes coupled with significant reductions in budgets for new hardware, software, training, and consulting. Perhaps your organization had grander plans, but now you find those plans on hold.

No astute DW/BI manager would be so shortsighted as to ignore these realities in the face of today's economic environment. But rather than just putting current activities on a budgetary crash diet, it's time to institute a proactive fitness program that will yield a leaner, more efficient and effective DW/BI program for the long haul. How can you do more in an environment where staffing and funding are constrained? You need to focus on three key opportunities:

  • Cost savings
  • Cost avoidance
  • Growth

Cut the Flab

In tough times, most organizations try to identify opportunities for cost savings. This often means significant reductions in budgets as well as possible staff reductions. We'll assume you are already running very lean; your budgets and staffing have already been evaluated and trimmed. After these obvious cuts, you'll want to look for other avenues to achieve cost savings.

Revisit the original justification for your DW/BI effort; often a number of cost savings goals were identified during the project justification effort. Have these goals been realized? If not, why not? Are the savings still available? If so, look for inexpensive methods that would help you achieve these goals.

Often the most significant cost savings assigned to a DW/BI effort are related to sunsetting older analytic environments, resulting in significant savings on hardware, software licenses, maintenance, and support resources. Try to determine why these savings have yet to be realized. We can often point the finger of blame at office politics. The new DW/BI environment may be well positioned to support the requirements of the existing analytic environment, yet a group of business users lacks the motivation to make the move. A mandate is required to force these stragglers to migrate to the new environment, and the current economic environment may provide just the incentive you need.

It's easy to just blame politics, but you need to talk to the holdout business users to understand their perspectives. The new solution may be almost everything these users need, but some vital component might still be missing. It could be very easy to solve the issue, perhaps with user training, a little applet or macro, modifications to reports, or possibly a minor change in the data or model.

Even in the best of times we want to sunset old applications, not only because of the operating costs but also because we want a single version of the truth. In these worst of times, we should be able to entice or force the stragglers to migrate away from the legacy environment to the new DW/BI solution and finally achieve the cost savings initially envisioned.

Monitor and Tune to Defer Spending

Organizations are also looking to defer planned costs. Perhaps in your surviving budget you have financial resources available to invest in additional hardware or software. Often, with a bit of creative thinking and hard work, these costs can be deferred or in some cases avoided altogether.

Inventory the software licenses you already have in place. Are they all being effectively used? Pay special attention to your BI tool licenses and how they are deployed. Many organizations find that the actual number of licenses in use is far below the number that have been deployed.

  • First, understand why the deployed licenses aren't being utilized. Perhaps there are low cost training or support investments that will help users become more effective, leverage the existing licenses, and enable your organization to achieve the anticipated benefits.
  • Second, if the licenses are not required where they were deployed, they should be shifted to other users. This realignment of licenses may allow you to defer a planned investment.
  • Worst case, if there is no current or future need for the licenses the maintenance can be discontinued and some cost savings achieved.

Similarly, cast a critical eye over the overall performance of your DW/BI environment. Often an investment in performance tuning can push a planned hardware upgrade a number of months into the future, ideally out of the current budget cycle. Query performance is highly visible, so start there:

  • Develop a log of system performance characteristics, if you're not already doing so. Your database systems and operating systems have features that enable you to capture a history of memory, disk, CPU usage, and other characteristics. You cannot tune performance if you don't understand performance.
  • Tune the SQL for all standard reports and other BI applications. This is the lowest hanging fruit because you can usually modify the query syntax, such as adding a hint, without changing the report's fundamental design.
  • Analyze the queries run in your environment looking for opportunities to improve your indexing and aggregation strategies. Tuning for ad hoc use continues to be something of an art form; you need to balance the value of an additional index against the cost of maintaining that index.
  • Work with your hardware/software vendors to ensure that you are leveraging the capabilities already available to you. Ask your vendors to provide known DW/BI best practices and tips.

After you've done what you can to squeeze every ounce of performance from the existing environment, consider whether moderate changes to your system design might provide substantial performance benefits. Your fact tables and their associated indexes and aggregates consume the most resources in your DW/BI environment. You may be surprised by how much query performance can be improved by reducing fact table and index size. Review your fact table designs and consider the following:

  • Replace all natural foreign keys with the smallest integer (surrogate) keys possible.
  • Combine correlated dimensions into single dimensions where possible.
  • Group tiny, low cardinality dimensions together, even if uncorrelated.
  • Take all text fields out of the fact table and make them dimensions, especially comment fields. It seems counterintuitive to make a dimension out of a high cardinality, analytically insignificant field like a comment, but the comment field is omitted from most queries. Removing the large character field from the fact table and replacing it with an integer key can make the fact table perform much more nimbly.
  • Replace long integer and floating point facts with scaled integers wherever possible.
  • If, contrary to our longstanding advice, your dimensions are normalized into snowflakes, collapse each into a denormalized, single table flat dimension table. You can often implement this as an additional step at the end of the ETL process.

Review your ETL system. Look for performance bottlenecks and identify ways to remove them. ETL teams often overlook indexing approaches in staging tables that might improve overall ETL performance. In addition, revisit the ETL logic from the early days of your DW/BI effort. The ETL team is now more experienced than it was in the beginning. Inevitably your team has identified more efficient and effective techniques than those initially implemented.

Bulk Up the Bottom Line

Most organizations initially justify their DW/BI initiatives citing opportunities to grow the business and improve productivity. The benefits identified are real and tangible, but they're often hard to quantify. It can be challenging to measure enhanced business results, such as increased revenue growth, improved profitability, greater customer acquisition/retention rates, or improved customer satisfaction.

Now's the time to revisit the proposed growth opportunities to evaluate whether the DW/BI environment has actually helped attain the benefits promised. If the benefits are being achieved, be sure to let the world know! There's nothing wrong with taking credit for a job well done. Your recent budget negotiations might have gone more smoothly if you had better records of the business value resulting from the DW/BI system. Start keeping those records now, even if they are just DBMS usage logs.

Most of us will recognize desired benefits that have not yet been fully realized. Investigate why these benefits continue to elude you. This analysis will require the DW/BI team to cast a critical eye over activities and results. Be brutally honest with yourself. Have you done everything required to help the organization achieve these benefits?

DW/BI teams often lose sight of the ultimate goal. They get so focused on getting the data into the data warehouse they forget about making it all the way to the finish line—enabling the business users to easily use the data for decision making. Consider refocusing some of your resources on achieving those benefits that provide significant value to the organization.

Look for low cost, incremental improvements you can make that offer substantive value to the organization:

  • Make sure you have documentation and training in place to help business people use the DW/BI system effectively.
  • Look for areas where the addition of a few dimension attributes or additional metrics to existing schema will enable valuable new analyses.
  • Look for opportunities to expose the existing portfolio of data and BI applications to a wider audience, perhaps tapping available software licenses identified as discussed earlier.
  • Work with key, analytic business users to evaluate the effectiveness of BI applications that have already been deployed. Look for opportunities to improve these existing BI applications to provide keener insights into the business. Seek out ways to better understand the analytic processes utilized by the savviest users in order to capture and extend these benefits to additional BI applications.
  • Enrich your data warehouse with new fact tables supporting additional business processes and new analytics.

It's unfortunate that the downturn in the economy has put many of us on an unwelcome budgetary diet, but we can also get lean and mean by hitting the gym and working out, figuratively speaking. We can focus carefully on our DW/BI environment's overall health and fitness and become far stronger and healthier for the long run.

14.12 Enjoy the Sunset

Bob Becker, Design Tip #143, Mar 1, 2012

Most organizations implementing a new data warehouse/business intelligence environment are replacing or “sunsetting” a legacy analytic/reporting system. This environment may be an older data warehouse, a single or series of departmental data marts, or a collection of analytic/reporting environments cobbled together using tools such as Access and Excel. Some may be officially sanctioned platforms; often they are shadow reporting environments crafted by a business unit. Regardless of the flavor, many business users rely on these environments for their reporting and analytic needs. Elimination of these disparate systems is a common goal of new DW/BI initiatives.

Elimination of these legacy/shadow systems often provides a significant amount of the hard dollar justification for the new DW/BI world. These savings result from the proposed elimination of hardware, software licenses, and associated maintenance and support costs. The hard dollar savings often include the manpower costs involved in reconciling data across multiple analytic platforms. In addition, there is often soft dollar justification based on the value of better integrated data, greater management confidence, and improved ease of use associated with replacing the legacy environments.

Unfortunately, sunsetting the legacy environments seldom occurs in a timely manner or often not at all, placing these justification dollars at risk. It's not uncommon to see an older legacy reporting environment running side by side with the new DW/BI environment far longer than was ever intended. Clearly, this is undesirable; if both environments continue to run, the hard dollar justification will never be recognized. At some point, management is going to look askew at this situation and begin questioning the integrity of the team responsible for the new DW/BI environment, potentially putting future funding at risk. In addition, most users will never embrace the new environment as long as the old environment continues to be available. Why change if you don't have to? As a result, there will continue to be data reconciliation challenges due to the multiple, inconsistent analytic and reporting platforms.

It is vital to the ongoing success of the new environment to avoid this situation. The DW/BI team needs to keep its eye on the goal, ensuring that each iteration helps move closer to sunsetting some portion of the legacy environment. At some point, it is often just a matter of having the courage to actually turn something off that is no longer needed. Before sunsetting an older environment you must completely understand the requirements that must be supported by the replacement DW/BI system:

  • Are all of the data and capabilities in place to support the current reports/analyses?
  • Are there other non-analytic functions that the older environment is supporting?
  • Does the existing system provide certain capabilities, such as auditing and compliance, which are not available elsewhere?
  • Are there downstream environments dependent on data from the legacy environment?

All of these requirements have a valid claim against the existing environment. Thus, you can't sunset the environment until you can support these requirements. At a recent client, the old analytic platform included a series of daily replicated copies of the production source. The primary purpose of these tables was to support the ETL change data capture process required to populate the environment. However, unbeknownst to the DW/BI team, some key users had obtained access to the replicated tables. They included these tables as a critical component of several data governance, data quality, and internal audit processes. When the DW/BI team attempted to shut down the old system, they found they couldn't as they had no alternate capability for supporting these requirements. Similarly, an analytic platform may find itself feeding other downstream purposes it may be totally unaware of. Again, be sure you have alternate solutions in place to support these requirements.

Once you are confident you have addressed the legacy system's support of analytics and reporting, non-DW/BI usage, and downstream application requirements, it's time to turn that system off! Of course, you may want to keep it processing for a few weeks while you shut off all external access and feeds from the system just to make sure you've got everything covered. Clearly, you'll want to get past a month end close to see if anything breaks.

A final technical/legal issue is whether you have full rights to expose the data from the old system once you have terminated its license. While you can probably argue that the data itself belongs to you, you may not be able to use the old system any more to generate reports on the old data. In such a case, you may have to dump your data into a neutral format before your right to use the underlying application terminates.

Once you're comfortable you've got all your bases covered, it's time—mix up some margaritas, pull the plug, and enjoy the sunset!

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