Gathering Performance Information
With release 7.2, the PostgreSQL developers introduced a new collection of performance-related system views. These views return two distinct kinds of information. The pg_statviews characterize the frequency and type of access for each table in a database. The pg_statio views will tell you how much physical I/O is performed on behalf of each table.
Let's look at each set of performance-related views in more detail.
The pg_stat_all_tables contains one row for each table in your database. Here is the layout of pg_stat_all_tables:
perf=# \d pg_stat_all_tables View "pg_stat_all_tables" Column | Type | Modifiers ---------------+---------+----------- relid | oid | schemaname | name | relname | name | seq_scan | bigint ...