PostgreSQL 12 文檔: 系統目錄

第 51 章 系統目錄

目錄

51.1. 概述

51.2. pg_aggregate

51.3. pg_am

51.4. pg_amop

51.5. pg_amproc

51.6. pg_attrdef

51.7. pg_attribute

51.8. pg_authid

51.9. pg_auth_members

51.10. pg_cast

51.11. pg_class

51.12. pg_collation

51.13. pg_constraint

51.14. pg_conversion

51.15. pg_database

51.16. pg_db_role_setting

51.17. pg_default_acl

51.18. pg_depend

51.19. pg_description

51.20. pg_enum

51.21. pg_event_trigger

51.22. pg_extension

51.23. pg_foreign_data_wrapper

51.24. pg_foreign_server

51.25. pg_foreign_table

51.26. pg_index

51.27. pg_inherits

51.28. pg_init_privs

51.29. pg_language

51.30. pg_largeobject

51.31. pg_largeobject_metadata

51.32. pg_namespace

51.33. pg_opclass

51.34. pg_operator

51.35. pg_opfamily

51.36. pg_partitioned_table

51.37. pg_pltemplate

51.38. pg_policy

51.39. pg_proc

51.40. pg_publication

51.41. pg_publication_rel

51.42. pg_range

51.43. pg_replication_origin

51.44. pg_rewrite

51.45. pg_seclabel

51.46. pg_sequence

51.47. pg_shdepend

51.48. pg_shdescription

51.49. pg_shseclabel

51.50. pg_statistic

51.51. pg_statistic_ext

51.52. pg_statistic_ext_data

51.53. pg_subscription

51.54. pg_subscription_rel

51.55. pg_tablespace

51.56. pg_transform

51.57. pg_trigger

51.58. pg_ts_config

51.59. pg_ts_config_map

51.60. pg_ts_dict

51.61. pg_ts_parser

51.62. pg_ts_template

51.63. pg_type

51.64. pg_user_mapping

51.65. 系統視圖

51.66. pg_available_extensions

51.67. pg_available_extension_versions

51.68. pg_config

51.69. pg_cursors

51.70. pg_file_settings

51.71. pg_group

51.72. pg_hba_file_rules

51.73. pg_indexes

51.74. pg_locks

51.75. pg_matviews

51.76. pg_policies

51.77. pg_prepared_statements

51.78. pg_prepared_xacts

51.79. pg_publication_tables

51.80. pg_replication_origin_status

51.81. pg_replication_slots

51.82. pg_roles

51.83. pg_rules

51.84. pg_seclabels

51.85. pg_sequences

51.86. pg_settings

51.87. pg_shadow

51.88. pg_stats

51.89. pg_stats_ext

51.90. pg_tables

51.91. pg_timezone_abbrevs

51.92. pg_timezone_names

51.93. pg_user

51.94. pg_user_mappings

51.95. pg_views

系統目錄是關係型資料庫存放模式元數據的地方，比如表和列的信息，以及內部統計信息等。PostgreSQL的系統目錄就是普通表。你可以刪除並重建這些表、增加列、插入和更新數值， 然後徹底把你的系統搞垮。 通常情況下，我們不應該手工修改系統目錄，通常有SQL命令可以做這些事情。（例如，CREATE DATABASE向 pg_database表插入一行 — 並且實際上在磁碟上創建該資料庫。）。 有幾種特別深奧的操作例外，但是隨著時間的流逝其中的很多也可以用 SQL 命令來完成，因此對系統目錄直接修改的需求也越來越小。