guorongtao

SQL 判断表、字段是否存在的方法(MSSQL Server、Oracle、MySQL、PostgreSql)

SQL 判断表、字段是否存在的方法(MSSQL Server、Oracle、MySQL、PostgreSql)

 1、MSSQL Server

select  count(*)  from  dbo.sysobjects where name=  \'表名\';  --  表
select  count(*)  from syscolumns where id=object_id(‘表名’)  and name=  \'字段名\';  --  字段 

2、Oracle

select count(*) from user_objects where  object_name =  \'表名\';  --  表
select count(*) from user_tab_columns where table_name = \'表名\' and column_name = \'字段名\';   --  字段

3、MySQL

select table_name from information_schema.tables where table_name =\'表名\';    --  表
select count(*) from information_schema.columns where table_name = \'表名\' and column_name = \'字段名\'   --  字段

4、PostgreSql

select count(*) from information_schema.tables where table_schema=\'table_schema\' and  table_name =\'表名\';  --  表
select count(*) from information_schema.columns where table_schema=\'table_schema\' and table_name =\'表名\' and  column_name=\'字段名\'; --  字段

5、其他往期扩展  链接

 

 

创建时间:2021.11.09  更新时间:

 

分类:

技术点:

相关文章: