openGauss gsql 常用元命令 一

openGauss gsql 常用元命令 一

连接数据库 使用 -E 参数可以显示元命令具体执行的 SQL 信息

[omm@og1 ~]$ gsql -d postgres -p15400 -E
gsql ((openGauss 2.1.0 build 590b0f8e) compiled at 2021-09-30 14:29:04 commit 0 last mr  )
Non-SSL connection (SSL connection is recommended when requiring high-security)
Type "help" for help.

\l 显示数据库中数据库信息

openGauss=# \l
********* QUERY **********
SELECT d.datname as "Name",pg_catalog.pg_get_userbyid(d.datdba) as "Owner",pg_catalog.pg_encoding_to_char(d.encoding) as "Encoding",d.datcollate as "Collate",d.datctype as "Ctype",pg_catalog.array_to_string(d.datacl, E'\n') AS "Access privileges"
FROM pg_catalog.pg_database d
ORDER BY 1;
**************************List of databasesName    | Owner | Encoding |  Collate   |   Ctype    | Access privileges
-----------+-------+----------+------------+------------+-------------------mydb      | omm   | UTF8     | en_US.utf8 | en_US.utf8 |postgres  | omm   | UTF8     | en_US.utf8 | en_US.utf8 |studentdb | omm   | UTF8     | en_US.utf8 | en_US.utf8 |template0 | omm   | UTF8     | en_US.utf8 | en_US.utf8 | =c/omm           +|       |          |            |            | omm=CTc/ommtemplate1 | omm   | UTF8     | en_US.utf8 | en_US.utf8 | =c/omm           +|       |          |            |            | omm=CTc/omm
(5 rows)

\du 同\dg 显示数据库中所有用户和角色

openGauss=# \du
********* QUERY **********
SELECT r.rolname, r.rolsuper, r.rolinherit,r.rolcreaterole, r.rolcreatedb, r.rolcanlogin,r.rolconnlimit, r.rolvalidbegin, r.rolvaliduntil,ARRAY(SELECT b.rolnameFROM pg_catalog.pg_auth_members mJOIN pg_catalog.pg_roles b ON (m.roleid = b.oid)WHERE m.member = r.oid) as memberof
, r.rolreplication
, r.rolauditadmin
, r.rolsystemadmin
, r.rolmonitoradmin
, r.roloperatoradmin
, r.rolpolicyadmin
, r.roluseft
, r.rolkind
FROM pg_catalog.pg_roles r
WHERE r.rolname not in ('gs_role_copy_files', 'gs_role_signal_backend', 'gs_role_tablespace', 'gs_role_replication', 'gs_role_account_lock', 'gs_role_pldebugger')
ORDER BY 1;
**************************List of rolesRole name |                                                    Attributes                                                    | Member of
-----------+------------------------------------------------------------------------------------------------------------------+-----------omm       | Sysadmin, Create role, Create DB, Replication, Administer audit, Monitoradmin, Operatoradmin, Policyadmin, UseFT | {}student   | Sysadmin                                                                                                         | {}openGauss=# \dg
********* QUERY **********
SELECT r.rolname, r.rolsuper, r.rolinherit,r.rolcreaterole, r.rolcreatedb, r.rolcanlogin,r.rolconnlimit, r.rolvalidbegin, r.rolvaliduntil,ARRAY(SELECT b.rolnameFROM pg_catalog.pg_auth_members mJOIN pg_catalog.pg_roles b ON (m.roleid = b.oid)WHERE m.member = r.oid) as memberof
, r.rolreplication
, r.rolauditadmin
, r.rolsystemadmin
, r.rolmonitoradmin
, r.roloperatoradmin
, r.rolpolicyadmin
, r.roluseft
, r.rolkind
FROM pg_catalog.pg_roles r
WHERE r.rolname not in ('gs_role_copy_files', 'gs_role_signal_backend', 'gs_role_tablespace', 'gs_role_replication', 'gs_role_account_lock', 'gs_role_pldebugger')
ORDER BY 1;
**************************List of rolesRole name |                                                    Attributes                                                    | Member of
-----------+------------------------------------------------------------------------------------------------------------------+-----------omm       | Sysadmin, Create role, Create DB, Replication, Administer audit, Monitoradmin, Operatoradmin, Policyadmin, UseFT | {}student   | Sysadmin                                                                                                         | {}

\db 显示数据库中所有表空间信息

openGauss=# \db
********* QUERY **********
SELECT spcname AS "Name",pg_catalog.pg_get_userbyid(spcowner) AS "Owner",pg_catalog.pg_tablespace_location(oid) AS "Location"
FROM pg_catalog.pg_tablespace
ORDER BY 1;
**************************List of tablespacesName    | Owner |        Location
------------+-------+------------------------pg_default | omm   |pg_global  | omm   |student_ts | omm   | tablespace/student_ts1
(3 rows)

\dn 显示数据库中所有 schema 信息

openGauss=# \dn
********* QUERY **********
SELECT n.nspname AS "Name",pg_catalog.pg_get_userbyid(n.nspowner) AS "Owner"
FROM pg_catalog.pg_namespace n
WHERE n.nspname !~ '^pg_' AND n.nspname <> 'information_schema'
ORDER BY 1;
**************************List of schemasName      |  Owner
----------------+---------blockchain     | ommcstore         | ommdb4ai          | ommdbe_perf       | ommdbe_pldebugger | ommpkg_service    | ommpmk            | ommpublic         | ommsnapshot       | ommsqladvisor     | ommstudent        | student
(11 rows)

\d 显示当前数据库下相关数据库对象信息(包含表、视图、物化视图、序列、外部表、stream\ contview)

openGauss=# \d
********* QUERY **********
SELECT n.nspname as "Schema",c.relname as "Name",CASE c.relkind WHEN 'r' THEN 'table' WHEN 'v' THEN 'view' WHEN 'i' THEN 'index' WHEN 'I' THEN 'global partition index' WHEN 'S' THEN 'sequence' WHEN 's' THEN 'special' WHEN 'f' THEN 'foreign table' WHEN 'm' THEN 'materialized view'  WHEN 'e' THEN 'stream' WHEN 'o' THEN 'contview' END as "Type",pg_catalog.pg_get_userbyid(c.relowner) as "Owner",c.reloptions as "Storage"
FROM pg_catalog.pg_class cLEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHERE c.relkind IN ('r','v','m','S','f','e','o','')AND n.nspname <> 'pg_catalog'AND n.nspname <> 'db4ai'AND n.nspname <> 'information_schema'AND n.nspname !~ '^pg_toast'AND c.relname not like 'matviewmap_%'AND c.relname not like 'mlog_%'AND pg_catalog.pg_table_is_visible(c.oid)
ORDER BY 1,2;
**************************List of relationsSchema |  Name  | Type  | Owner |             Storage
--------+--------+-------+-------+----------------------------------public | test   | table | omm   | {orientation=row,compression=no}public | v_test | view  | omm   |
(2 rows)

\d tablename 查看某个表的详细信息

openGauss=# \d test
********* QUERY **********
SELECT c.oid,n.nspname,c.relname
FROM pg_catalog.pg_class cLEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHERE c.relname ~ '^(test)$'AND pg_catalog.pg_table_is_visible(c.oid)
ORDER BY 2, 3;
*********************************** QUERY **********
SELECT c.relchecks, c.relkind, c.relhasindex, c.relhasrules, c.relhastriggers, c.relhasoids, '', c.reltablespace, CASE WHEN c.reloftype = 0 THEN '' ELSE c.reloftype::pg_catalog.regtype::pg_catalog.text END, c.relpersistence,c.relhasclusterkey, c.relreplident, (select count(1) as haspolicy from pg_catalog.pg_class WHERE relname = 'pg_rlspolicy')
FROM pg_catalog.pg_class cLEFT JOIN pg_catalog.pg_class tc ON (c.reltoastrelid = tc.oid)
WHERE c.oid = '16575';
*********************************** QUERY **********
SELECT * FROM pg_catalog.pg_class WHERE relname = 'gs_encrypted_columns' AND relnamespace = 11;
*********************************** QUERY **********
SELECT a.attname,pg_catalog.format_type(a.atttypid, a.atttypmod),(SELECT substring(pg_catalog.pg_get_expr(d.adbin, d.adrelid) for 176)FROM pg_catalog.pg_attrdef dWHERE d.adrelid = a.attrelid AND d.adnum = a.attnum AND a.atthasdef),a.attnotnull, a.attnum,(SELECT c.collname FROM pg_catalog.pg_collation c, pg_catalog.pg_type tWHERE c.oid = a.attcollation AND t.oid = a.atttypid AND a.attcollation <> t.typcollation) AS attcollation,NULL AS indexdef,NULL AS attfdwoptions,(SELECT pg_catalog.format_type (a.atttypmod, g.data_type_original_mod) AS clientlogic_original_type FROM  gs_encrypted_columns g WHERE g.column_name = a.attname  AND g.rel_id = 16575group by g.data_type_original_oid, g.data_type_original_mod),
(SELECT g.data_type_original_oid AS clientlogic_original_type_oid FROM  gs_encrypted_columns g WHERE g.column_name = a.attname  AND g.rel_id = 16575group by g.data_type_original_oid, g.data_type_original_mod),(SELECT  h.adgencolFROM pg_catalog.pg_attrdef hWHERE h.adrelid = a.attrelid AND h.adnum = a.attnum AND a.atthasdef) AS generated_column
FROM pg_catalog.pg_attribute a
WHERE a.attrelid = '16575' AND a.attnum > 0 AND NOT a.attisdropped AND a.attkvtype != 4 AND a.attname <> 'tableoid' AND a.attname <> 'tablebucketid'
ORDER BY a.attnum;
*********************************** QUERY **********
SELECT c2.relname, i.indisprimary, i.indisunique, i.indisclustered, i.indisvalid, pg_catalog.pg_get_indexdef(i.indexrelid, 0, true),pg_catalog.pg_get_constraintdef(con.oid, true), contype, condeferrable, condeferred, i.indisreplident, c2.reltablespace, i.indisusable
FROM pg_catalog.pg_class c, pg_catalog.pg_class c2, pg_catalog.pg_index iLEFT JOIN pg_catalog.pg_constraint con ON (conrelid = i.indrelid AND conindid = i.indexrelid AND contype IN ('p','u','x'))
WHERE c.oid = '16575' AND c.oid = i.indrelid AND i.indexrelid = c2.oid
ORDER BY i.indisprimary DESC, i.indisunique DESC, c2.relname;
*********************************** QUERY **********
SELECT pol.policyname, pol.policypermissive, trim(pol.policyroles::text, '{}'), pol.policyqual, pol.policycmd
FROM pg_catalog.pg_rlspolicies pol
LEFT JOIN pg_catalog.pg_namespace N on (N.nspname = pol.schemaname)
LEFT JOIN pg_catalog.pg_class C on (pol.tablename = C.relname and C.relnamespace = N.oid)
WHERE C.oid = '16575' ORDER BY 1;
*********************************** QUERY **********
SELECT c.oid::pg_catalog.regclass FROM pg_catalog.pg_class c, pg_catalog.pg_inherits i WHERE c.oid=i.inhparent AND i.inhrelid = '16575' ORDER BY inhseqno;
*********************************** QUERY **********
SELECT c.oid::pg_catalog.regclass FROM pg_catalog.pg_class c, pg_catalog.pg_inherits i WHERE c.oid=i.inhrelid AND i.inhparent = '16575' ORDER BY c.oid::pg_catalog.regclass::pg_catalog.text;
*********************************** QUERY **********
select partkey,partstrategy from pg_partition where parentid = 16575 order by partkey
**************************Table "public.test"Column |  Type   | Modifiers
--------+---------+-----------id     | integer |
Indexes:"idx_id_test" btree (id) TABLESPACE pg_defaultopenGauss=#

\dt 显示当前数据库中所有的表

openGauss=# \dt
********* QUERY **********
SELECT n.nspname as "Schema",c.relname as "Name",CASE c.relkind WHEN 'r' THEN 'table' WHEN 'v' THEN 'view' WHEN 'i' THEN 'index' WHEN 'I' THEN 'global partition index' WHEN 'S' THEN 'sequence' WHEN 's' THEN 'special' WHEN 'f' THEN 'foreign table' WHEN 'm' THEN 'materialized view'  WHEN 'e' THEN 'stream' WHEN 'o' THEN 'contview' END as "Type",pg_catalog.pg_get_userbyid(c.relowner) as "Owner",c.reloptions as "Storage"
FROM pg_catalog.pg_class cLEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHERE c.relkind IN ('r','')AND n.nspname <> 'pg_catalog'AND n.nspname <> 'db4ai'AND n.nspname <> 'information_schema'AND n.nspname !~ '^pg_toast'AND c.relname not like 'matviewmap_%'AND c.relname not like 'mlog_%'AND pg_catalog.pg_table_is_visible(c.oid)
ORDER BY 1,2;
**************************List of relationsSchema | Name | Type  | Owner |             Storage
--------+------+-------+-------+----------------------------------public | test | table | omm   | {orientation=row,compression=no}
(1 row)

\dt+ 以扩展方式显示当前数据库所有表信息,比起\dt 多了最后一列描述信息

openGauss=# \dt+
********* QUERY **********
SELECT n.nspname as "Schema",c.relname as "Name",CASE c.relkind WHEN 'r' THEN 'table' WHEN 'v' THEN 'view' WHEN 'i' THEN 'index' WHEN 'I' THEN 'global partition index' WHEN 'S' THEN 'sequence' WHEN 's' THEN 'special' WHEN 'f' THEN 'foreign table' WHEN 'm' THEN 'materialized view'  WHEN 'e' THEN 'stream' WHEN 'o' THEN 'contview' END as "Type",pg_catalog.pg_get_userbyid(c.relowner) as "Owner",pg_catalog.pg_size_pretty(pg_catalog.pg_table_size(c.oid)) as "Size",c.reloptions as "Storage",pg_catalog.obj_description(c.oid, 'pg_class') as "Description"
FROM pg_catalog.pg_class cLEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHERE c.relkind IN ('r','')AND n.nspname <> 'pg_catalog'AND n.nspname <> 'db4ai'AND n.nspname <> 'information_schema'AND n.nspname !~ '^pg_toast'AND c.relname not like 'matviewmap_%'AND c.relname not like 'mlog_%'AND pg_catalog.pg_table_is_visible(c.oid)
ORDER BY 1,2;
**************************List of relationsSchema | Name | Type  | Owner |  Size   |             Storage              | Description
--------+------+-------+-------+---------+----------------------------------+-------------public | test | table | omm   | 0 bytes | {orientation=row,compression=no} |
(1 row)

\di 查看当前数据库中索引信息

openGauss=# \di
********* QUERY **********
SELECT n.nspname as "Schema",c.relname as "Name",CASE c.relkind WHEN 'r' THEN 'table' WHEN 'v' THEN 'view' WHEN 'i' THEN 'index' WHEN 'I' THEN 'global partition index' WHEN 'S' THEN 'sequence' WHEN 's' THEN 'special' WHEN 'f' THEN 'foreign table' WHEN 'm' THEN 'materialized view'  WHEN 'e' THEN 'stream' WHEN 'o' THEN 'contview' END as "Type",pg_catalog.pg_get_userbyid(c.relowner) as "Owner",c2.relname as "Table",c.reloptions as "Storage"
FROM pg_catalog.pg_class cLEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespaceLEFT JOIN pg_catalog.pg_index i ON i.indexrelid = c.oidLEFT JOIN pg_catalog.pg_class c2 ON i.indrelid = c2.oid
WHERE c.relkind IN ('i','I','')AND n.nspname <> 'pg_catalog'AND n.nspname <> 'db4ai'AND n.nspname <> 'information_schema'AND n.nspname !~ '^pg_toast'AND c.relname not like 'matviewmap_%'AND c.relname not like 'mlog_%'AND pg_catalog.pg_table_is_visible(c.oid)
ORDER BY 1,2;
**************************List of relationsSchema |    Name     | Type  | Owner | Table | Storage
--------+-------------+-------+-------+-------+---------public | idx_id_test | index | omm   | test  |
(1 row)

\di indexname 查看当前数据库某个索引的信息

openGauss=# \di idx_id_test
********* QUERY **********
SELECT n.nspname as "Schema",c.relname as "Name",CASE c.relkind WHEN 'r' THEN 'table' WHEN 'v' THEN 'view' WHEN 'i' THEN 'index' WHEN 'I' THEN 'global partition index' WHEN 'S' THEN 'sequence' WHEN 's' THEN 'special' WHEN 'f' THEN 'foreign table' WHEN 'm' THEN 'materialized view'  WHEN 'e' THEN 'stream' WHEN 'o' THEN 'contview' END as "Type",pg_catalog.pg_get_userbyid(c.relowner) as "Owner",c2.relname as "Table",c.reloptions as "Storage"
FROM pg_catalog.pg_class cLEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespaceLEFT JOIN pg_catalog.pg_index i ON i.indexrelid = c.oidLEFT JOIN pg_catalog.pg_class c2 ON i.indrelid = c2.oid
WHERE c.relkind IN ('i','I','s','')AND n.nspname !~ '^pg_toast'AND c.relname not like 'matviewmap_%'AND c.relname not like 'mlog_%'AND c.relname ~ '^(idx_id_test)$'AND pg_catalog.pg_table_is_visible(c.oid)
ORDER BY 1,2;
**************************List of relationsSchema |    Name     | Type  | Owner | Table | Storage
--------+-------------+-------+-------+-------+---------public | idx_id_test | index | omm   | test  |
(1 row)

\dv 查看当前数据库视图信息

openGauss=# \dv
********* QUERY **********
SELECT n.nspname as "Schema",c.relname as "Name",CASE c.relkind WHEN 'r' THEN 'table' WHEN 'v' THEN 'view' WHEN 'i' THEN 'index' WHEN 'I' THEN 'global partition index' WHEN 'S' THEN 'sequence' WHEN 's' THEN 'special' WHEN 'f' THEN 'foreign table' WHEN 'm' THEN 'materialized view'  WHEN 'e' THEN 'stream' WHEN 'o' THEN 'contview' END as "Type",pg_catalog.pg_get_userbyid(c.relowner) as "Owner",c.reloptions as "Storage"
FROM pg_catalog.pg_class cLEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHERE c.relkind IN ('v','')AND n.nspname <> 'pg_catalog'AND n.nspname <> 'db4ai'AND n.nspname <> 'information_schema'AND n.nspname !~ '^pg_toast'AND c.relname not like 'matviewmap_%'AND c.relname not like 'mlog_%'AND pg_catalog.pg_table_is_visible(c.oid)
ORDER BY 1,2;
**************************List of relationsSchema |  Name  | Type | Owner | Storage
--------+--------+------+-------+---------public | v_test | view | omm   |
(1 row)

\ds 查看当前数据库序列信息

openGauss=# \ds
********* QUERY **********
SELECT n.nspname as "Schema",c.relname as "Name",CASE c.relkind WHEN 'r' THEN 'table' WHEN 'v' THEN 'view' WHEN 'i' THEN 'index' WHEN 'I' THEN 'global partition index' WHEN 'S' THEN 'sequence' WHEN 's' THEN 'special' WHEN 'f' THEN 'foreign table' WHEN 'm' THEN 'materialized view'  WHEN 'e' THEN 'stream' WHEN 'o' THEN 'contview' END as "Type",pg_catalog.pg_get_userbyid(c.relowner) as "Owner",c.reloptions as "Storage"
FROM pg_catalog.pg_class cLEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHERE c.relkind IN ('S','')AND n.nspname <> 'pg_catalog'AND n.nspname <> 'db4ai'AND n.nspname <> 'information_schema'AND n.nspname !~ '^pg_toast'AND c.relname not like 'matviewmap_%'AND c.relname not like 'mlog_%'AND pg_catalog.pg_table_is_visible(c.oid)
ORDER BY 1,2;
**************************List of relationsSchema | Name |   Type   | Owner | Storage
--------+------+----------+-------+---------public | sq1  | sequence | omm   |
(1 row)

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