Greenplum常用SQL查询

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Greenplum常用SQL查询

2024-05-09 02:55| 来源: 网络整理| 查看: 265

抽空网上收罗Greenplum常用SQL查询语句整理备忘。欢迎各位留言补充。都是SQL命令以及数据字典的使用。熟悉数据字典非常重要。三个重要的schema:pg_catalog,pg_toolkit,information_schema,其中information_schema 中的数据字典都在视图中

目录一、查看表某模式所有分布键信息二、数据库运行状态查询管理1.greenplum查询正在运行的sql，session2.终止执行的sql3.查看greemplum资源队列状态4.查看greemplum资源队列锁5.查看greemplum资源队列优先级6.查看greemplum所有连接类似mysql SHOW PROCESSLIST7.greemplum磁盘使用，通过SQL查看Greenplum中用了多少空间8.查看greemplum节点状态9.节点故障等历史信息10.数据倾斜11.greemplum表或索引大小（占用空间）12.greemplum表和索引大小（占用空间）13.greemplum查看指定数据库大小（占用空间）14.greemplum所有数据库大小（占用空间）15.查看greemplum数据分布情况三、查源数据16.查看greemplum数据表更新时间17.通过sql 获取greemplum表的预估数据量18.通过sql 获取greemplum获取分布键19.通过sql获取 greemplum指定表结构20.显示哪些没有统计信息且可能需要ANALYZE的表21.显示在系统表中被标记为掉线的Segment的信息22.显示库中表的大小（单位G）23.查询一个库中有多少表（如果有分区表不列出子分区）24.查询某个用户对某个表有什么权限25.查看分区表的信息26.导入数据27.远程导入数据28.导数据指定分隔符（和mysql的select into outfile很像）29.生成授权语句30 .给用户授权31、改变postgreSQL的默认schema

一、查看表某模式所有分布键信息

SELECT aaa.nspname AS "模式名", aaa.relname AS "表名", aaa.table_comment AS "中文表明", ccc.attname AS "分布键" FROM ( SELECT aa.oid, obj_description (aa.oid) AS table_comment, aa.relname, bb.localoid, bb.attrnums, regexp_split_to_table ( array_to_string (bb.attrnums, ','), ',' ) att, dd.nspname FROM pg_class aa --原数据信息最重要的表！ LEFT JOIN gp_distribution_policy bb ON bb.localoid = aa.oid --分布键表 LEFT JOIN pg_namespace dd ON dd.oid = aa.relnamespace --模式 LEFT JOIN pg_inherits hh ON aa.oid = hh.inhrelid --继承表 WHERE dd.nspname = 'dim' -- 替换成需要的模式 AND hh.inhrelid IS NULL ) aaa LEFT JOIN pg_attribute ccc ON ccc.attrelid = aaa.oid AND ccc.attnum = aaa.att WHERE ccc.attnum > 0 ORDER BY aaa.relname;

二、数据库运行状态查询管理

1.greenplum查询正在运行的sql，session

-- 方法1： SELECT tt.procpid, -- pid usename user_name, -- 执行的用户 backend_start, -- 会话开始时间 query_start, -- 查询开始时间 waiting, -- 是否等待执行 now() - query_start AS current_query_time, -- 累计执行时间 now() - backend_start AS current_session_time,*/ current_query, client_addr , datname FROM pg_stat_activity tt WHERE current_query != '' ORDER BY current_query_time DESC; -- 方法2（通过视图查） SELECT procpid, START, now() - START AS lap, current_query, -- count() over() count_num, t2.rolname,t3.rsqname, ip FROM ( SELECT backendid, pg_stat_get_backend_userid(S.backendid) as uid, pg_stat_get_backend_client_addr(S.backendid) as ip, pg_stat_get_backend_pid (S.backendid) AS procpid, pg_stat_get_backend_activity_start (S.backendid) AS START, pg_stat_get_backend_activity (S.backendid) AS current_query FROM ( SELECT pg_stat_get_backend_idset () AS backendid ) AS S ) AS t1 left join pg_authid t2 on t1.uid=t2.oid left join pg_resqueue t3 on t2.rolresqueue=t3.oid WHERE current_query!= '' ORDER BY lap DESC; -- 方法3（限定了角色和资源队列，查当前账号正在查询的语句） SELECT rolname, rsqname, pid, GRANTED, current_query, datname FROM pg_roles t1, gp_toolkit.gp_resqueue_status t2 , pg_locks t3 , pg_stat_activity t4 WHERE t1.rolresqueue = t3.objid AND t3.objid=t2.queueid and t4.procpid=t3.pid

2.终止执行的sql

select pg_terminate_backend(48988); --pid

3.查看greemplum资源队列状态

SELECT * FROM gp_toolkit.gp_resqueue_status;

4.查看greemplum资源队列锁

SELECT * FROM gp_toolkit.gp_locks_on_resqueue WHERE lorwaiting='true';

5.查看greemplum资源队列优先级

select * from gp_toolkit.gp_resq_priority_statement;

6.查看greemplum所有连接类似mysql SHOW PROCESSLIST

select * from pg_stat_activity; -- 所有状态的连接

7.greemplum磁盘使用，通过SQL查看Greenplum中用了多少空间

select datname,pg_size_pretty(pg_database_size(datname)) from pg_database;

8.查看greemplum节点状态

select * from gp_segment_configuration tt select * from gp_segment_configuration tt where tt.status='d'; -- 状态为down

9.节点故障等历史信息

select * from gp_configuration_history tt order by 1 desc ;

10.数据倾斜

SELECT t1.gp_segment_id, t1.count_tatol, round(t1.count_tatol-(AVG(t1.count_tatol) over()) ,0) FROM ( SELECT gp_segment_id, COUNT (*) count_tatol FROM -- 要查的表 GROUP BY gp_segment_id ) t1 order by 3

11.greemplum表或索引大小（占用空间）

select pg_size_pretty(pg_relation_size('gp_test'));

12.greemplum表和索引大小（占用空间）

select pg_size_pretty(pg_total_relation_size('gp_test'));

13.greemplum查看指定数据库大小（占用空间）

select pg_size_pretty(pg_database_size('postgres'));

14.greemplum所有数据库大小（占用空间）

select datname,pg_size_pretty(pg_database_size(datname)) from pg_database;

15.查看greemplum数据分布情况

select gp_segment_id,count(*) from gp_test group by gp_segment_id order by 1;

三、查源数据

16.查看greemplum数据表更新时间

SELECT * FROM pg_stat_last_operation, pg_class WHERE objid = oid AND relname = 'base_common'; -- 表名

17.通过sql 获取greemplum表的预估数据量

select relname, reltuples::int as total from pg_class where relname = 'base_common' and relnamespace = (select oid from pg_namespace where nspname = 'positions');

18.通过sql 获取greemplum获取分布键

SELECT string_agg(att.attname,',' order by attrnums) as distribution FROM gp_distribution_policy a,pg_attribute att WHERE a.localoid ='bi_data.schoolmate_relations'::regclass and a.localoid = att.attrelid and att.attnum = any(a.attrnums);

19.通过sql获取 greemplum指定表结构

SELECT attname, typname FROM pg_attribute INNER JOIN pg_class ON pg_attribute.attrelid = pg_class.oid INNER JOIN pg_type ON pg_attribute.atttypid = pg_type.oid INNER JOIN pg_namespace on pg_class.relnamespace=pg_namespace.oid -- WHERE pg_attribute.attnum > 0 AND attisdropped 't' AND pg_namespace.nspname='resumes' AND pg_class.relname= 'base_common' -- and pg_class.relname ~~* any(array['%some%', '%someelse'])); order by pg_attribute.attnum

20.显示哪些没有统计信息且可能需要ANALYZE的表

SELECT * from gp_toolkit.gp_stats_missing ;

21.显示在系统表中被标记为掉线的Segment的信息

SELECT * from gp_toolkit.gp_pgdatabase_invalid;

22.显示库中表的大小（单位G）

SELECT sotdoid,sotdsize/1024/1024/1024 as sotdsize,sotdtoastsize,sotdadditionalsize,sotdschemaname,sotdtablename from gp_toolkit.gp_size_of_table_disk order by sotdsize desc;

23.查询一个库中有多少表（如果有分区表不列出子分区）

SELECT relname from pg_class a,pg_namespace b where relname not like '%prt%' and relkind ='r' and a.relnamespace=b.oid and nspname not in ('pg_catalog','information_schema','gp_toolkit') and nspname not like '%pg_temp%';

24.查询某个用户对某个表有什么权限

select * from INFORMATION_SCHEMA.role_table_grants where grantee='user_name' and table_name='table';

25.查看分区表的信息

SELECT tablename,partitiontablename,partitiontype,partitionboundary from pg_partitions where tablename='table_name' order by partitionboundary desc;

26.导入数据

copy t1 from '/home/gpadmin/t1.txt' with delimiter '|' LOG ERRORS INTO INSERT_ERRS SEGMENT REJECT LIMIT 100;

27.远程导入数据

psql -h 1.1.1.1 -U user_name -d db_name -W -c "copy tb1 from stdin with delimiter '|'" < /home/gpadmin/tb1.txt

28.导数据指定分隔符（和mysql的select into outfile很像）

psql -d db_name -c "select * from tb1" -o tb1.txt -t -A -F $'/t'

29.生成授权语句

SELECT 'grant select on '||relname||' to user_name;' from pg_class a,pg_namespace b where relname not like '%prt%' and relkind ='r' and has_table_privilege('user_name',a.oid,'select')='f' and a.relnamespace=b.oid and nspname not in ('pg_catalog','information_schema','gp_toolkit') and nspname not like '%pg_temp%';

30 .给用户授权

select 'grant all on SCHEMA ' || tt.autnspname || ' to tuser;' as grant_script from gp_toolkit.__gp_user_tables tt -- group by tt.autnspname union -- all select 'grant all on table ' || tt.autnspname || '.' ||tt.autrelname || ' to tuser;' grant_script from gp_toolkit.__gp_user_tables tt;

31、改变postgreSQL的默认schema

-- Use this to show the current search_path -- Should return: "$user",public SHOW search_path; -- Create another schema CREATE SCHEMA my_schema; GRANT ALL ON SCHEMA my_schema TO my_user; -- To change search_path on a connection-level SET search_path TO my_schema; -- To change search_path on a database-level ALTER database "my_database" SET search_path TO my_schema;

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