if exists(select 1 from syscolumns where id=object_id('TableName') where name='xx') ...
if not exists(select 1 from sys.columns a inner join sys.objects b on a.object_id=b.object_id and a.name='yourcolumnname' and b.name='yourtablename') alter table yourtablename add yourcolumnname columntype
IF NOT EXISTS(SELECT * FROM sys.columns WHERE Name='列名' AND object_id('表名')) ALTER TABLE 表名 ADD 列名 int
举个例子,create table t4(i int)-- 判断j列是否存在,不存在则添加. if col_length('t4','j') is null alter table t4 add j int-- 查看结果. select object_name(id) table_name, name col_names from syscolumns where id=object_id('t4')table_name col_names ------------------------- t4 i t4 j
少了列IF NOT EXISTS(SELECT * FROM sys.columns WHERE Name='列名' AND object_id=object_id('表名')) ALTER TABLE 表名 ADD 列名 int
...
alter table yourtablename add yourcolumnname columntype
ALTER TABLE 表名 ADD 列名 int
if col_length('t4','j') is null
alter table t4 add j int-- 查看结果.
select object_name(id) table_name,
name col_names
from syscolumns
where id=object_id('t4')table_name col_names
-------------------------
t4 i
t4 j
ALTER TABLE 表名 ADD 列名 int