数据库 
首页 > 数据库 > 浏览文章

pgsql 实现用户自定义表结构信息获取

(编辑:jimmy 日期: 2024/11/5 浏览:3 次 )

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

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: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

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;

以上为个人经验,希望能给大家一个参考,也希望大家多多支持。如有错误或未考虑完全的地方,望不吝赐教。

上一篇:postgresql重置序列起始值的操作
下一篇:PostgreSQL批量修改函数拥有者的操作
一句话新闻
一文看懂荣耀MagicBook Pro 16
荣耀猎人回归!七大亮点看懂不只是轻薄本,更是游戏本的MagicBook Pro 16.
人们对于笔记本电脑有一个固有印象:要么轻薄但性能一般,要么性能强劲但笨重臃肿。然而,今年荣耀新推出的MagicBook Pro 16刷新了人们的认知——发布会上,荣耀宣布猎人游戏本正式回归,称其继承了荣耀 HUNTER 基因,并自信地为其打出“轻薄本,更是游戏本”的口号。
众所周知,寻求轻薄本的用户普遍更看重便携性、外观造型、静谧性和打字办公等用机体验,而寻求游戏本的用户则普遍更看重硬件配置、性能释放等硬核指标。把两个看似难以相干的产品融合到一起,我们不禁对它产生了强烈的好奇:作为代表荣耀猎人游戏本的跨界新物种,它究竟做了哪些平衡以兼顾不同人群的各类需求呢?
友情链接:杰晶网络 DDR爱好者之家 南强小屋 黑松山资源网 白云城资源网 SiteMap