52.64. System Views

In addition to the system catalogs, PostgreSQL provides a number of built-in views. Some system views provide convenient access to some commonly used queries on the system catalogs. Other views provide access to internal server state.

The information schema ( Chapter 37 ) provides an alternative set of views which overlap the functionality of the system views. Since the information schema is SQL-standard whereas the views described here are PostgreSQL -specific, it's usually better to use the information schema if it provides all the information you need.

Table 52.65 lists the system views described here. More detailed documentation of each view follows below. There are some additional views that provide access to the results of the statistics collector; they are described in Table 28.2 .

Except where noted, all the views described here are read-only.

Table 52.65. System Views

View Name Purpose
pg_available_extensions available extensions
pg_available_extension_versions available versions of extensions
pg_backend_memory_contexts backend memory contexts
pg_config compile-time configuration parameters
pg_cursors open cursors
pg_file_settings summary of configuration file contents
pg_group groups of database users
pg_hba_file_rules summary of client authentication configuration file contents
pg_indexes indexes
pg_locks locks currently held or awaited
pg_matviews materialized views
pg_policies policies
pg_prepared_statements prepared statements
pg_prepared_xacts prepared transactions
pg_publication_tables publications and their associated tables
pg_replication_origin_status information about replication origins, including replication progress
pg_replication_slots replication slot information
pg_roles database roles
pg_rules rules
pg_seclabels security labels
pg_sequences sequences
pg_settings parameter settings
pg_shadow database users
pg_shmem_allocations shared memory allocations
pg_stats planner statistics
pg_stats_ext extended planner statistics
pg_stats_ext_exprs extended planner statistics for expressions
pg_tables tables
pg_timezone_abbrevs time zone abbreviations
pg_timezone_names time zone names
pg_user database users
pg_user_mappings user mappings
pg_views views