本篇文章给大家分享的是有关 怎么在pgsql中利用自定义表结构获取信息,小编觉得挺实用的,因此分享给大家学习,希望大家阅读完这篇文章后可以有所收获,话不多说,跟着小编一起来看看吧。
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SELECT column_name, data_type, ordinal_position, is_nullable FROM information_schema."columns" WHERE "table_name"='TABLE-NAME' -- 将 'TABLE-NAME' 换成自己的表
2.获取所有的表和视图
SELECT table_name, table_type FROM INFORMATION_SCHEMA.tables WHERE table_schema='public' AND table_type IN ('BASE TABLE','VIEW')
3.获取约束注释
SELECT obj_description(oid, 'pg_constraint') AS d FROM pg_constraint WHERE conname = constraint_name;
4.获取表的约束
-- conname 约束名称 -- contype 约束类型(p:主键, f:外键, c: 检查约束, u:约束) -- conkey 约束字段 -- confkey 外键字段 -- consrc 检查约束条件 -- confreltable 外键字段引用的表 SELECT conname, contype, conkey, consrc, (SELECT array_agg(column_name::text) FROM INFORMATION_SCHEMA.COLUMNS WHERE ordinal_position = any(conkey) AND table_name= 'TABLE-NAME') AS conkey, (SELECT column_name FROM INFORMATION_SCHEMA.COLUMNS WHERE ordinal_position = any(confkey) AND table_name='TABLE-NAME') AS confkey, (SELECT relname FROM pg_class WHERE oid = confrelid) AS confreltable FROM pg_constraint WHERE conrelid=(SELECT oid FROM pg_class WHERE relname ='TABLE-NAME'); -- 将 'TABLE-NAME' 换成自己的表
5.获取表的触发器
SELECT trigger_name, event_manipulation, event_object_table, action_statement, action_orientation, action_timing FROM INFORMATION_SCHEMA.TRIGGERS;
6.获取字段的注释
--table_oid 表的oid --col_position 字段的位置 SELECT col_description(table_oid, col_position);
补充:查询PostgreSQL库中所有表的表结构信息SQL
我就废话不多说了,大家还是直接看代码吧~
select (select relname as comment from pg_class where oid=a.attrelid) as table_name, row_number() over(partition by (select relname as comment from pg_class where oid=a.attrelid) order by a.attnum), a.attname as column_name, format_type(a.atttypid,a.atttypmod) as data_type, (case when atttypmod-4>0 then atttypmod-4 else 0 end)data_length, (case when (select count(*) from pg_constraint where conrelid = a.attrelid and conkey[1]=attnum and contype='p')>0 then '是' else '否' end) as 主键约束, (case when (select count(*) from pg_constraint where conrelid = a.attrelid and conkey[1]=attnum and contype='u')>0 then '是' else '否' end) as 约束, (case when (select count(*) from pg_constraint where conrelid = a.attrelid and conkey[1]=attnum and contype='f')>0 then '是' else '否' end) as 外键约束, (case when a.attnotnull=true then '是' else '否' end) as nullable, col_description(a.attrelid,a.attnum) as comment from pg_attribute a where attstattarget=-1 and attrelid in (select oid from pg_class where relname in(select relname from pg_class where relkind ='r' and relname in (select tablename from pg_tables where tablename not like 'pg_%' and tablename not like 'sql_%' and schemaname not in(XXXX) and tablename not in(XXXX) )) order by table_name,a.attnum;
以上就是 怎么在pgsql中利用自定义表结构获取信息,小编相信有部分知识点可能是我们日常工作会见到或用到的。希望你能通过这篇文章学到更多知识。更多详情敬请关注创新互联行业资讯频道。