System Catalogs

Table of Contents
49.1. Overview
49.2. pg_aggregate
49.3. pg_am
49.4. pg_amop
49.5. pg_amproc
49.6. pg_attrdef
49.7. pg_attribute
49.8. pg_authid
49.9. pg_auth_members
49.10. pg_cast
49.11. pg_class
49.12. pg_collation
49.13. pg_constraint
49.14. pg_conversion
49.15. pg_database
49.16. pg_db_role_setting
49.17. pg_default_acl
49.18. pg_depend
49.19. pg_description
49.20. pg_enum
49.21. pg_event_trigger
49.22. pg_extension
49.23. pg_foreign_data_wrapper
49.24. pg_foreign_server
49.25. pg_foreign_table
49.26. pg_index
49.27. pg_inherits
49.28. pg_language
49.29. pg_largeobject
49.30. pg_largeobject_metadata
49.31. pg_namespace
49.32. pg_opclass
49.33. pg_operator
49.34. pg_opfamily
49.35. pg_pltemplate
49.36. pg_policy
49.37. pg_proc
49.38. pg_range
49.39. pg_replication_origin
49.40. pg_rewrite
49.41. pg_seclabel
49.42. pg_shdepend
49.43. pg_shdescription
49.44. pg_shseclabel
49.45. pg_statistic
49.46. pg_tablespace
49.47. pg_transform
49.48. pg_trigger
49.49. pg_ts_config
49.50. pg_ts_config_map
49.51. pg_ts_dict
49.52. pg_ts_parser
49.53. pg_ts_template
49.54. pg_type
49.55. pg_user_mapping
49.56. System Views
49.57. pg_available_extensions
49.58. pg_available_extension_versions
49.59. pg_cursors
49.60. pg_file_settings
49.61. pg_group
49.62. pg_indexes
49.63. pg_locks
49.64. pg_matviews
49.65. pg_policies
49.66. pg_prepared_statements
49.67. pg_prepared_xacts
49.68. pg_replication_origin_status
49.69. pg_replication_slots
49.70. pg_roles
49.71. pg_rules
49.72. pg_seclabels
49.73. pg_settings
49.74. pg_shadow
49.75. pg_stats
49.76. pg_tables
49.77. pg_timezone_abbrevs
49.78. pg_timezone_names
49.79. pg_user
49.80. pg_user_mappings
49.81. pg_views

The system catalogs are the place where a relational database management system stores schema metadata, such as information about tables and columns, and internal bookkeeping information. PostgreSQL 's system catalogs are regular tables. You can drop and recreate the tables, add columns, insert and update values, and severely mess up your system that way. Normally, one should not change the system catalogs by hand, there are always SQL commands to do that. (For example, CREATE DATABASE inserts a row into the pg_database catalog - and actually creates the database on disk.) There are some exceptions for particularly esoteric operations, such as adding index access methods.