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PostgreSQL深入浅出 | 数据库的日常维护

2022-12-07 数据库加入收藏

1、概述

本篇是继上一篇笔记《课程笔记 | PostgreSQL深入浅出 | 数据库的启动与停止》的续集，本篇主要介绍PostgreSQL数据库的日常基本操作。后续也会持续更新内容。

2、查看数据库版本

[postgres@localhost ~]$ pg_ctl -V

pg_ctl (PostgreSQL) 12.12

3、登录数据库

[postgres@localhost ~]$ psql -d postgres

psql (12.12)

Type "help" for help.

postgres=#

4、列出所有数据库

postgres=# l

5、显示所有用户

postgres=# du

6、查看扩展

postgres=# dx

7、列出表和视图的信息

postgres=# dS

List of relations

Schema | Name | Type | Owner

------------+---------------------------------+-------+----------

pg_catalog | pg_aggregate | table | postgres

pg_catalog | pg_am | table | postgres

pg_catalog | pg_amop | table | postgres

pg_catalog | pg_amproc | table | postgres

pg_catalog | pg_attrdef | table | postgres

pg_catalog | pg_attribute | table | postgres

pg_catalog | pg_auth_members | table | postgres

pg_catalog | pg_authid | table | postgres

pg_catalog | pg_available_extension_versions | view | postgres

pg_catalog | pg_available_extensions | view | postgres

pg_catalog | pg_cast | table | postgres

pg_catalog | pg_class | table | postgres

pg_catalog | pg_collation | table | postgres

pg_catalog | pg_config | view | postgres

pg_catalog | pg_constraint | table | postgres

pg_catalog | pg_conversion | table | postgres

pg_catalog | pg_cursors | view | postgres

pg_catalog | pg_database | table | postgres

pg_catalog | pg_db_role_setting | table | postgres

pg_catalog | pg_default_acl | table | postgres

pg_catalog | pg_depend | table | postgres

pg_catalog | pg_description | table | postgres

pg_catalog | pg_enum | table | postgres

pg_catalog | pg_event_trigger | table | postgres

pg_catalog | pg_extension | table | postgres

pg_catalog | pg_file_settings | view | postgres

pg_catalog | pg_foreign_data_wrapper | table | postgres

pg_catalog | pg_foreign_server | table | postgres

pg_catalog | pg_foreign_table | table | postgres

pg_catalog | pg_group | view | postgres

pg_catalog | pg_hba_file_rules | view | postgres

pg_catalog | pg_index | table | postgres

pg_catalog | pg_indexes | view | postgres

pg_catalog | pg_inherits | table | postgres

pg_catalog | pg_init_privs | table | postgres

pg_catalog | pg_language | table | postgres

pg_catalog | pg_largeobject | table | postgres

pg_catalog | pg_largeobject_metadata | table | postgres

pg_catalog | pg_locks | view | postgres

pg_catalog | pg_matviews | view | postgres

pg_catalog | pg_namespace | table | postgres

pg_catalog | pg_opclass | table | postgres

pg_catalog | pg_operator | table | postgres

pg_catalog | pg_opfamily | table | postgres

pg_catalog | pg_partitioned_table | table | postgres

pg_catalog | pg_pltemplate | table | postgres

pg_catalog | pg_policies | view | postgres

pg_catalog | pg_policy | table | postgres

pg_catalog | pg_prepared_statements | view | postgres

pg_catalog | pg_prepared_xacts | view | postgres

pg_catalog | pg_proc | table | postgres

pg_catalog | pg_publication | table | postgres

pg_catalog | pg_publication_rel | table | postgres

pg_catalog | pg_publication_tables | view | postgres

pg_catalog | pg_range | table | postgres

pg_catalog | pg_replication_origin | table | postgres

pg_catalog | pg_replication_origin_status | view | postgres

pg_catalog | pg_replication_slots | view | postgres

pg_catalog | pg_rewrite | table | postgres

pg_catalog | pg_roles | view | postgres

pg_catalog | pg_rules | view | postgres

pg_catalog | pg_seclabel | table | postgres

pg_catalog | pg_seclabels | view | postgres

pg_catalog | pg_sequence | table | postgres

pg_catalog | pg_sequences | view | postgres

pg_catalog | pg_settings | view | postgres

pg_catalog | pg_shadow | view | postgres

pg_catalog | pg_shdepend | table | postgres

pg_catalog | pg_shdescription | table | postgres

pg_catalog | pg_shseclabel | table | postgres

pg_catalog | pg_stat_activity | view | postgres

pg_catalog | pg_stat_all_indexes | view | postgres

pg_catalog | pg_stat_all_tables | view | postgres

pg_catalog | pg_stat_archiver | view | postgres

pg_catalog | pg_stat_bgwriter | view | postgres

pg_catalog | pg_stat_database | view | postgres

pg_catalog | pg_stat_database_conflicts | view | postgres

pg_catalog | pg_stat_gssapi | view | postgres

pg_catalog | pg_stat_progress_cluster | view | postgres

pg_catalog | pg_stat_progress_create_index | view | postgres

pg_catalog | pg_stat_progress_vacuum | view | postgres

pg_catalog | pg_stat_replication | view | postgres

pg_catalog | pg_stat_ssl | view | postgres

pg_catalog | pg_stat_subscription | view | postgres

pg_catalog | pg_stat_sys_indexes | view | postgres

pg_catalog | pg_stat_sys_tables | view | postgres

pg_catalog | pg_stat_user_functions | view | postgres

pg_catalog | pg_stat_user_indexes | view | postgres

pg_catalog | pg_stat_user_tables | view | postgres

pg_catalog | pg_stat_wal_receiver | view | postgres

pg_catalog | pg_stat_xact_all_tables | view | postgres

pg_catalog | pg_stat_xact_sys_tables | view | postgres

pg_catalog | pg_stat_xact_user_functions | view | postgres

pg_catalog | pg_stat_xact_user_tables | view | postgres

pg_catalog | pg_statio_all_indexes | view | postgres

pg_catalog | pg_statio_all_sequences | view | postgres

pg_catalog | pg_statio_all_tables | view | postgres

pg_catalog | pg_statio_sys_indexes | view | postgres

pg_catalog | pg_statio_sys_sequences | view | postgres

pg_catalog | pg_statio_sys_tables | view | postgres

pg_catalog | pg_statio_user_indexes | view | postgres

pg_catalog | pg_statio_user_sequences | view | postgres

pg_catalog | pg_statio_user_tables | view | postgres

pg_catalog | pg_statistic | table | postgres

pg_catalog | pg_statistic_ext | table | postgres

pg_catalog | pg_statistic_ext_data | table | postgres

pg_catalog | pg_stats | view | postgres

pg_catalog | pg_stats_ext | view | postgres

pg_catalog | pg_subscription | table | postgres

pg_catalog | pg_subscription_rel | table | postgres

pg_catalog | pg_tables | view | postgres

pg_catalog | pg_tablespace | table | postgres

pg_catalog | pg_timezone_abbrevs | view | postgres

pg_catalog | pg_timezone_names | view | postgres

pg_catalog | pg_transform | table | postgres

pg_catalog | pg_trigger | table | postgres

pg_catalog | pg_ts_config | table | postgres

pg_catalog | pg_ts_config_map | table | postgres

pg_catalog | pg_ts_dict | table | postgres

pg_catalog | pg_ts_parser | table | postgres

pg_catalog | pg_ts_template | table | postgres

pg_catalog | pg_type | table | postgres

pg_catalog | pg_user | view | postgres

pg_catalog | pg_user_mapping | table | postgres

pg_catalog | pg_user_mappings | view | postgres

pg_catalog | pg_views | view | postgres

(126 rows)

postgres=#

补充：postgres=# dS+ 显示了更多信息，包括表的大小信息。

8、查看数据库端口号

postgres=# show port;

9、查看表空间

postgres=# db+

10、列出所有模式

postgres=# dn

11、查看数据库的表

postgres=# dt

12、查看表字段

postgres=# d {{tablename}}

13、创建一个数据库

CREATE DATABASE DBTEST1;

14、切换数据库

postgres=# c dbtest1

15、显示所有帮助信息

dbtest1=# h

Available help:

ABORT CHECKPOINT CREATE USER DROP TRIGGER

ALTER AGGREGATE CLOSE CREATE USER MAPPING DROP TYPE

ALTER COLLATION CLUSTER CREATE VIEW DROP USER

ALTER CONVERSION COMMENT DEALLOCATE DROP USER MAPPING

ALTER DATABASE COMMIT DECLARE DROP VIEW

ALTER DEFAULT PRIVILEGES COMMIT PREPARED DELETE END

ALTER DOMAIN COPY DISCARD EXECUTE

ALTER EVENT TRIGGER CREATE ACCESS METHOD DO EXPLAIN

ALTER EXTENSION CREATE AGGREGATE DROP ACCESS METHOD FETCH

ALTER FOREIGN DATA WRAPPER CREATE CAST DROP AGGREGATE GRANT

ALTER FOREIGN TABLE CREATE COLLATION DROP CAST IMPORT FOREIGN SCHEMA

ALTER FUNCTION CREATE CONVERSION DROP COLLATION INSERT

ALTER GROUP CREATE DATABASE DROP CONVERSION LISTEN

ALTER INDEX CREATE DOMAIN DROP DATABASE LOAD

ALTER LANGUAGE CREATE EVENT TRIGGER DROP DOMAIN LOCK

ALTER LARGE OBJECT CREATE EXTENSION DROP EVENT TRIGGER MOVE

ALTER MATERIALIZED VIEW CREATE FOREIGN DATA WRAPPER DROP EXTENSION NOTIFY

ALTER OPERATOR CREATE FOREIGN TABLE DROP FOREIGN DATA WRAPPER PREPARE

ALTER OPERATOR CLASS CREATE FUNCTION DROP FOREIGN TABLE PREPARE TRANSACTION

ALTER OPERATOR FAMILY CREATE GROUP DROP FUNCTION REASSIGN OWNED

ALTER POLICY CREATE INDEX DROP GROUP REFRESH MATERIALIZED VIEW

ALTER PROCEDURE CREATE LANGUAGE DROP INDEX REINDEX

ALTER PUBLICATION CREATE MATERIALIZED VIEW DROP LANGUAGE RELEASE SAVEPOINT

ALTER ROLE CREATE OPERATOR DROP MATERIALIZED VIEW RESET

ALTER ROUTINE CREATE OPERATOR CLASS DROP OPERATOR REVOKE

ALTER RULE CREATE OPERATOR FAMILY DROP OPERATOR CLASS ROLLBACK

ALTER SCHEMA CREATE POLICY DROP OPERATOR FAMILY ROLLBACK PREPARED

ALTER SEQUENCE CREATE PROCEDURE DROP OWNED ROLLBACK TO SAVEPOINT

ALTER SERVER CREATE PUBLICATION DROP POLICY SAVEPOINT

ALTER STATISTICS CREATE ROLE DROP PROCEDURE SECURITY LABEL

ALTER SUBSCRIPTION CREATE RULE DROP PUBLICATION SELECT

ALTER SYSTEM CREATE SCHEMA DROP ROLE SELECT INTO

ALTER TABLE CREATE SEQUENCE DROP ROUTINE SET

ALTER TABLESPACE CREATE SERVER DROP RULE SET CONSTRAINTS

ALTER TEXT SEARCH CONFIGURATION CREATE STATISTICS DROP SCHEMA SET ROLE

ALTER TEXT SEARCH DICTIONARY CREATE SUBSCRIPTION DROP SEQUENCE SET SESSION AUTHORIZATION

ALTER TEXT SEARCH PARSER CREATE TABLE DROP SERVER SET TRANSACTION

ALTER TEXT SEARCH TEMPLATE CREATE TABLE AS DROP STATISTICS SHOW

ALTER TRIGGER CREATE TABLESPACE DROP SUBSCRIPTION START TRANSACTION

ALTER TYPE CREATE TEXT SEARCH CONFIGURATION DROP TABLE TABLE

ALTER USER CREATE TEXT SEARCH DICTIONARY DROP TABLESPACE TRUNCATE

ALTER USER MAPPING CREATE TEXT SEARCH PARSER DROP TEXT SEARCH CONFIGURATION UNLISTEN

ALTER VIEW CREATE TEXT SEARCH TEMPLATE DROP TEXT SEARCH DICTIONARY UPDATE

ANALYZE CREATE TRANSFORM DROP TEXT SEARCH PARSER VACUUM

BEGIN CREATE TRIGGER DROP TEXT SEARCH TEMPLATE VALUES

CALL CREATE TYPE DROP TRANSFORM WITH

dbtest1=#

16、显示创建表的帮助信息

dbtest1=# h create table

Command: CREATE TABLE

Description: define a new table

Syntax:

CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } | UNLOGGED ] TABLE [ IF NOT EXISTS ] table_name ( [

{ column_name data_type [ COLLATE collation ] [ column_constraint [ ... ] ]

| table_constraint

| LIKE source_table [ like_option ... ] }

[, ... ]

] )

[ INHERITS ( parent_table [, ... ] ) ]

[ PARTITION BY { RANGE | LIST | HASH } ( { column_name | ( expression ) } [ COLLATE collation ] [ opclass ] [, ... ] ) ]

[ USING method ]

[ WITH ( storage_parameter [= value] [, ... ] ) | WITHOUT OIDS ]

[ ON COMMIT { PRESERVE ROWS | DELETE ROWS | DROP } ]

[ TABLESPACE tablespace_name ]

CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } | UNLOGGED ] TABLE [ IF NOT EXISTS ] table_name

OF type_name [ (

{ column_name [ WITH OPTIONS ] [ column_constraint [ ... ] ]

| table_constraint }

[, ... ]

) ]

[ PARTITION BY { RANGE | LIST | HASH } ( { column_name | ( expression ) } [ COLLATE collation ] [ opclass ] [, ... ] ) ]

[ USING method ]

[ WITH ( storage_parameter [= value] [, ... ] ) | WITHOUT OIDS ]

[ ON COMMIT { PRESERVE ROWS | DELETE ROWS | DROP } ]

[ TABLESPACE tablespace_name ]

CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } | UNLOGGED ] TABLE [ IF NOT EXISTS ] table_name

PARTITION OF parent_table [ (

{ column_name [ WITH OPTIONS ] [ column_constraint [ ... ] ]

| table_constraint }

[, ... ]

) ] { FOR VALUES partition_bound_spec | DEFAULT }

[ PARTITION BY { RANGE | LIST | HASH } ( { column_name | ( expression ) } [ COLLATE collation ] [ opclass ] [, ... ] ) ]

dbtest1=#

17、显示ALTER TABLE的帮助信息

dbtest1=# h ALTER TABLE

Command: ALTER TABLE

Description: change the definition of a table

Syntax:

ALTER TABLE [ IF EXISTS ] [ ONLY ] name [ * ]

action [, ... ]

ALTER TABLE [ IF EXISTS ] [ ONLY ] name [ * ]

RENAME [ COLUMN ] column_name TO new_column_name

ALTER TABLE [ IF EXISTS ] [ ONLY ] name [ * ]

RENAME CONSTRAINT constraint_name TO new_constraint_name

ALTER TABLE [ IF EXISTS ] name

RENAME TO new_name

ALTER TABLE [ IF EXISTS ] name

SET SCHEMA new_schema

ALTER TABLE ALL IN TABLESPACE name [ OWNED BY role_name [, ... ] ]

SET TABLESPACE new_tablespace [ NOWAIT ]

ALTER TABLE [ IF EXISTS ] name

ATTACH PARTITION partition_name { FOR VALUES partition_bound_spec | DEFAULT }

ALTER TABLE [ IF EXISTS ] name

DETACH PARTITION partition_name

where action is one of:

ADD [ COLUMN ] [ IF NOT EXISTS ] column_name data_type [ COLLATE collation ] [ column_constraint [ ... ] ]

DROP [ COLUMN ] [ IF EXISTS ] column_name [ RESTRICT | CASCADE ]

ALTER [ COLUMN ] column_name [ SET DATA ] TYPE data_type [ COLLATE collation ] [ USING expression ]

ALTER [ COLUMN ] column_name SET DEFAULT expression

ALTER [ COLUMN ] column_name DROP DEFAULT

ALTER [ COLUMN ] column_name { SET | DROP } NOT NULL

ALTER [ COLUMN ] column_name ADD GENERATED { ALWAYS | BY DEFAULT } AS IDENTITY [ ( sequence_options ) ]

ALTER [ COLUMN ] column_name { SET GENERATED { ALWAYS | BY DEFAULT } | SET sequence_option | RESTART [ [ WITH ] restart ] } [...]

ALTER [ COLUMN ] column_name DROP IDENTITY [ IF EXISTS ]

ALTER [ COLUMN ] column_name SET STATISTICS integer

ALTER [ COLUMN ] column_name SET ( attribute_option = value [, ... ] )

ALTER [ COLUMN ] column_name RESET ( attribute_option [, ... ] )

ALTER [ COLUMN ] column_name SET STORAGE { PLAIN | EXTERNAL | EXTENDED | MAIN }

ADD table_constraint [ NOT VALID ]

ADD table_constraint_using_index

ALTER CONSTRAINT constraint_name [ DEFERRABLE | NOT DEFERRABLE ] [ INITIALLY DEFERRED | INITIALLY IMMEDIATE ]

VALIDATE CONSTRAINT constraint_name

DROP CONSTRAINT [ IF EXISTS ] constraint_name [ RESTRICT | CASCADE ]

DISABLE TRIGGER [ trigger_name | ALL | USER ]

ENABLE TRIGGER [ trigger_name | ALL | USER ]

ENABLE REPLICA TRIGGER trigger_name

ENABLE ALWAYS TRIGGER trigger_name

DISABLE RULE rewrite_rule_name

ENABLE RULE rewrite_rule_name

ENABLE REPLICA RULE rewrite_rule_name

ENABLE ALWAYS RULE rewrite_rule_name

DISABLE ROW LEVEL SECURITY

ENABLE ROW LEVEL SECURITY

FORCE ROW LEVEL SECURITY

NO FORCE ROW LEVEL SECURITY

CLUSTER ON index_name

SET WITHOUT CLUSTER

SET WITHOUT OIDS

SET TABLESPACE new_tablespace

SET { LOGGED | UNLOGGED }

SET ( storage_parameter [= value] [, ... ] )

RESET ( storage_parameter [, ... ] )

INHERIT parent_table

NO INHERIT parent_table

OF type_name

NOT OF

OWNER TO { new_owner | CURRENT_USER | SESSION_USER }

REPLICA IDENTITY { DEFAULT | USING INDEX index_name | FULL | NOTHING }

and partition_bound_spec is:

IN ( partition_bound_expr [, ...] ) |

FROM ( { partition_bound_expr | MINVALUE | MAXVALUE } [, ...] )

TO ( { partition_bound_expr | MINVALUE | MAXVALUE } [, ...] ) |

WITH ( MODULUS numeric_literal, REMAINDER numeric_literal )

and column_constraint is:

[ CONSTRAINT constraint_name ]

{ NOT NULL |

NULL |

CHECK ( expression ) [ NO INHERIT ] |

DEFAULT default_expr |

GENERATED ALWAYS AS ( generation_expr ) STORED |

GENERATED { ALWAYS | BY DEFAULT } AS IDENTITY [ ( sequence_options ) ] |

UNIQUE index_parameters |

PRIMARY KEY index_parameters |

REFERENCES reftable [ ( refcolumn ) ] [ MATCH FULL | MATCH PARTIAL | MATCH SIMPLE ]

[ ON DELETE referential_action ] [ ON UPDATE referential_action ] }

[ DEFERRABLE | NOT DEFERRABLE ] [ INITIALLY DEFERRED | INITIALLY IMMEDIATE ]

and table_constraint is:

[ CONSTRAINT constraint_name ]

{ CHECK ( expression ) [ NO INHERIT ] |

UNIQUE ( column_name [, ... ] ) index_parameters |

PRIMARY KEY ( column_name [, ... ] ) index_parameters |

EXCLUDE [ USING index_method ] ( exclude_element WITH operator [, ... ] ) index_parameters [ WHERE ( predicate ) ] |

FOREIGN KEY ( column_name [, ... ] ) REFERENCES reftable [ ( refcolumn [, ... ] ) ]

[ MATCH FULL | MATCH PARTIAL | MATCH SIMPLE ] [ ON DELETE referential_action ] [ ON UPDATE referential_action ] }

[ DEFERRABLE | NOT DEFERRABLE ] [ INITIALLY DEFERRED | INITIALLY IMMEDIATE ]

and table_constraint_using_index is:

[ CONSTRAINT constraint_name ]

{ UNIQUE | PRIMARY KEY } USING INDEX index_name

[ DEFERRABLE | NOT DEFERRABLE ] [ INITIALLY DEFERRED | INITIALLY IMMEDIATE ]

index_parameters in UNIQUE, PRIMARY KEY, and EXCLUDE constraints are:

[ INCLUDE ( column_name [, ... ] ) ]

[ WITH ( storage_parameter [= value] [, ... ] ) ]

[ USING INDEX TABLESPACE tablespace_name ]

exclude_element in an EXCLUDE constraint is:

{ column_name | ( expression ) } [ opclass ] [ ASC | DESC ] [ NULLS { FIRST | LAST } ]

URL: https://www.postgresql.org/docs/12/sql-altertable.html

dbtest1=#

18、查询数据库的链接信息

postgres=# select * from pg_stat_activity;

19、查询数据库中已经存在的用户和角色

postgres=# select * from pg_stat_activity;

postgres=# SELECT rolname FROM pg_roles;

20、退出数据库

postgres=# q