=========== PostgreSQL ==============
数据库名
SELECT datname FROM pg_database
得到所有用户自定义表的名字
select tablename from pg_tables where schemaname=public
列名
select COLUMN_NAME from information_schema.columns where table_name = 'users'
===========================
Oracle中查看所有表和字段
https://www.cnblogs.com/kongxc/p/9395148.html
获取表字段：
select *
from user_tab_columns
where Table_Name='用户表'
order by column_name
获取表注释：
select *
from user_tab_comments
where Table_Name='用户表'
order by Table_Name
获取字段注释：
select *
from user_col_comments
where Table_Name='用户表'
order by column_name
/* 获取表：*/
select table_name from user_tables; //当前用户的表
select table_name from all_tables; //所有用户的表
select table_name from dba_tables; //包括系统表
select table_name from dba_tables where owner='zfxfzb'
/*
user_tables：
table_name,tablespace_name,last_analyzed等
dba_tables：
ower,table_name,tablespace_name,last_analyzed等
all_tables：
ower,table_name,tablespace_name,last_analyzed等
all_objects：
ower,object_name,subobject_name,object_id,created,last_ddl_time,timestamp,status等
*/
/* 获取表字段：*/
select * from user_tab_columns where Table_Name='用户表';
select * from all_tab_columns where Table_Name='用户表';
select * from dba_tab_columns where Table_Name='用户表';
/* user_tab_columns：
table_name,column_name,data_type,data_length,data_precision,data_scale,nullable,column_id等
all_tab_columns ：
ower,table_name,column_name,data_type,data_length,data_precision,data_scale,nullable,column_id等
dba_tab_columns：
ower,table_name,column_name,data_type,data_length,data_precision,data_scale,nullable,column_id等
*/
/* 获取表注释：*/
select * from user_tab_comments
/*
user_tab_comments：table_name,table_type,comments
相应的还有dba_tab_comments，all_tab_comments，这两个比user_tab_comments多了ower列。
*/
/* 获取字段注释：*/
select * from user_col_comments
/*
user_col_comments：table_name,column_name,comments
相应的还有dba_col_comments，all_col_comments，这两个比user_col_comments多了ower列。
*/
----------oracle查询所有表-------------
SELECT TABLE_NAME FROM all_tables
WHERE OWNER = 'PORTAL_HIS'
--and GLOBAL_STATS='NO'
ORDER BY table_name
----------oracle查询表字段-------------
SELECT COLUMN_NAME,DATA_TYPE FROM user_tab_columns where table_name = upper('BA_BAJY')
select * from all_users
----------sql查询所有表-------------
Select name From sysobjects where xtype='U'
----------sql查询表字段-------------
Select name from syscolumns Where ID=OBJECT_ID('tb')
----------sql查询表字段与类别-------------
select column_name,data_type from information_schema.columns
where table_name = 'tb'
----------sql创建临时表-------------
IF OBJECT_ID('dbo.#tablelist', 'U') IS NOT NULL
DROP TABLE dbo.#tablelist;
CREATE TABLE #tablelist
(
id int identity(1,1) primary key,
fieldnm varchar(200),
fieldty varchar(50),
fieldvalue varchar(200)
)
select * from #tablelist
================================================
-----查询库下的owner---
exec sp_helpuser
-----查询表---
Select "name",uid,xtype,category From sysobjects a
where xtype='u' or xtype='v' and category=0
