Design tips

• In IBM Db2 Warehouse SaaS, all tables are column organized by default for optimal performance on analytical workloads. While you can create row-organized tables, it is strongly recommended that you create all tables as column organized for good performance on analytical queries.

• As a SaaS offering, IBM Db2 Warehouse SaaS automatically manages table spaces, buffer pools, and database partition groups to ensure optimal performance. When you create your IBM Db2 Warehouse SaaS instance, you'll find the following database objects created by default:

  • One regular table space: USERSPACE1 (32K page size)
  • One temporary table space: TEMPSPACE1 (32K page size)
  • One buffer pool: IBMDEFAULTBP (32K page size)
  • One database partition group: IBMDEFAULTGROUP

  It is strongly recommended to not create additional table spaces, temporary table spaces, buffer pools, or database partition groups.

• If you’re using any one of the IBM Db2 Warehouse SaaS multi-partitioned plans, you can optimize performance by defining a good set of table distribution keys. A good distribution key distributes data evenly across database partitions so that all of your database partitions can help process data for your queries. A poorly-chosen distribution key results in data skew. This means that data is stored unevenly across database partitions such that only a subset of data partitions participate in the processing while the rest remain idle. For more information about distribution keys, see Distribution keys for multi-partitioned plans.

  If you’re using a single-partitioned plan, there’s no need to worry about distribution keys because all of the data is stored on one data partition.

• The Db2 engine includes many registry and environment variables, and database configuration parameters. As a SaaS offering, IBM Db2 Warehouse SaaS is deployed with preconfigured variables and parameters to optimize performance. Changing any of these settings might result in adverse effects on database operation or performance and is therefore strongly discouraged. If you think your system might benefit from changes to some registry variables, environment variables, or database configuration parameters, open a support case to request guidance from our service experts.