第 51 章 系统目录

目录

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_subscription
51.53. pg_subscription_rel
51.54. pg_tablespace
51.55. pg_transform
51.56. pg_trigger
51.57. pg_ts_config
51.58. pg_ts_config_map
51.59. pg_ts_dict
51.60. pg_ts_parser
51.61. pg_ts_template
51.62. pg_type
51.63. pg_user_mapping
51.64. System Views
51.65. pg_available_extensions
51.66. pg_available_extension_versions
51.67. pg_config
51.68. pg_cursors
51.69. pg_file_settings
51.70. pg_group
51.71. pg_hba_file_rules
51.72. pg_indexes
51.73. pg_locks
51.74. pg_matviews
51.75. pg_policies
51.76. pg_prepared_statements
51.77. pg_prepared_xacts
51.78. pg_publication_tables
51.79. pg_replication_origin_status
51.80. pg_replication_slots
51.81. pg_roles
51.82. pg_rules
51.83. pg_seclabels
51.84. pg_sequences
51.85. pg_settings
51.86. pg_shadow
51.87. pg_stats
51.88. pg_tables
51.89. pg_timezone_abbrevs
51.90. pg_timezone_names
51.91. pg_user
51.92. pg_user_mappings
51.93. pg_views

系统目录是关系型数据库存放模式元数据的地方,比如表和列的信息,以及内部统计信息等。PostgreSQL的系统目录就是普通表。你可以删除并重建这些表、增加列、插入和更新数值, 然后彻底把你的系统搞垮。 通常情况下,我们不应该手工修改系统目录,通常有SQL命令可以做这些事情。(例如,CREATE DATABASEpg_database表插入一行 — 并且实际上在磁盘上创建该数据库。)。 有几种特别深奥的操作例外,但是随着时间的流逝其中的很多也可以用 SQL 命令来完成,因此对系统目录直接修改的需求也越来越小。