pgsql 实现用户自定义表结构信息获取_PostgreSQL

pgsql 实现用户自定义表结构信息获取

2021-03-07 18:41_rtf PostgreSQL

这篇文章主要介绍了pgsql 实现用户自定义表结构信息获取，具有很好的参考价值，希望对大家有所帮助。一起跟随小编过来看看吧

1. 获取表中普通信息：如字段名，字段类型等

									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

1	`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

1	`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:唯一约束)

									-- 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

1	`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 唯一约束,

									(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;