48.75. System Views

In addition to the system catalogs, LightDB 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 35) 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 LightDB-specific, it's usually better to use the information schema if it provides all the information you need.

Table 48.76 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 26.2.

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

Table 48.76. System Views

View NamePurpose
pg_available_extensionsavailable extensions
pg_available_extension_versionsavailable versions of extensions
pg_configcompile-time configuration parameters
pg_cursorsopen cursors
pg_file_settingssummary of configuration file contents
pg_groupgroups of database users
pg_hba_file_rulessummary of client authentication configuration file contents
pg_indexesindexes
pg_lockslocks currently held or awaited
pg_policiespolicies
pg_prepared_statementsprepared statements
pg_prepared_xactsprepared transactions
pg_publication_tablespublications and their associated tables
pg_replication_origin_statusinformation about replication origins, including replication progress
pg_replication_slotsreplication slot information
pg_rolesdatabase roles
pg_rulesrules
pg_seclabelssecurity labels
pg_sequencessequences
pg_settingsparameter settings
pg_shadowdatabase users
pg_shmem_allocationsshared memory allocations
pg_statsplanner statistics
pg_stats_extextended planner statistics
pg_tablestables
pg_timezone_abbrevstime zone abbreviations
pg_timezone_namestime zone names
pg_userdatabase users
pg_user_mappingsuser mappings
pg_viewsviews