Collecting Statistics on Partitioned Tables

For partitioned tables, you can collect partition-level statistics, which can be queried in the pg_partition and pg_statistic system catalogs and in the pg_stats and pg_ext_stats views. Partition-level statistics apply to the scenario where the scanning range of a partitioned table is pruned to a single partition after static pruning is performed on the partitioned table. Partition-level statistics include the number of pages and tuples, single-column statistics, multi-column statistics, and expression index statistics.

You can collect statistics on partitioned tables in either of the following ways:

• Collecting statistics in cascading mode
• Collecting statistics on a specified partition

• Collecting Statistics in Cascading Mode
  
• Collecting Partition-Level Statistics