GCP provides several data storage systems, including the following:

• Cloud SQL: This is useful if we need a relational database with full SQL support for online transaction processing (OLTP)
• Cloud Bigtable: This is useful if we don't require support for ACID transactions
• BigQuery: This is useful if we need interactive querying in an online analytical processing (OLAP) system
• Cloud Storage: This is useful if we need to store large immutable blobs, such as large images or movies

In this exercise, we used Bigtable. In the I-IoT, we do not need support for transactions, but we prefer scalability optimization rather than complex query language.