258 IBM Cognos Dynamic Cubes
10.1 Dynamic Query Analyzer
Dynamic Query Analyzer provides Cognos report developers and system administrators with
the ability to visualize and review the composition of queries to a dynamic cube and the
relational source data the dynamic cube is established from.
Visualizations provided by Dynamic Query Analyzer assist in the understanding of queries
requested to satisfy a report, their cost, and their ability to take advantage of existing cached
information. Dynamic Query Analyzer can help identify performance impacts of report design
elements.
This chapter focuses on the features of Dynamic Query Analyzer that support troubleshooting
and investigation into Cognos Dynamic Cubes and their associated reports.
Dynamic Query Analyzer is the primary query visualization tool for Dynamic Query Mode, and
many of the areas discussed in this chapter can be applied to reports that are not based on
dynamic cubes.
10.1.1 New Features
The Dynamic Query Analyzer user interface is extended to support visualization and
troubleshooting capabilities for Dynamic Cubes. Some generic feature extensions were also
added.
Aggregate Advisor
Aggregate Advisor is a performance optimization utility that is embedded in Dynamic Query
Analyzer. You can use Aggregate Advisor to provide guidance on aggregate table definition
based on dynamic cube workload. Cognos Dynamic Cubes takes advantage of aggregate
table and in memory aggregate definitions for aggregated data results, optimizing query
performance. Aggregate Advisor is explored in Chapter 8, “Optimization and performance
tuning” on page 201.
This section reviews how Dynamic Query Analyzer provides tools to support the report author
and system administrator confirming query performance through the expected use of Cognos
Dynamic Cubes aggregate cache and the use of aggregate tables during query execution.
Cognos Dynamic Cubes query nodes
Dynamic Query Analyzer is extended to include Dynamic Cubes query nodes, which detail
the use of Dynamic Query caches and the SQL that is passed to an underlying data source
where a query is not satisfied from available cache.
The cube start process is also reviewed and how, with Dynamic Query Analyzer, we can
explore the cube-startup process and dimension member caching.
Chapter 2, “IBM Cognos Dynamic Cubes architecture” on page 9 details the architecture of
dynamic cubes, cache optimization, and the caching strategy used during query execution.
Report-based Dynamic Query logging
Dynamic Query Analyzer now supports the ability to apply changes to the logging level of
Dynamic Query Mode server component on an individual report run basis. Logging of the
server component for Dynamic Query traces server activity and is distinct from query
planning tracing and query execution tracing. Previously, the logging level of the server
component for Dynamic Query could only be amended on the Cognos 10 Business
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