if exists(select * from syscolumns where id=object_id(’表名’) and name=’列名’) alter table 表名drop column 列名 判断列是否自增列 if columnproperty(object_id(’table’),’col’,’IsIdentity’)=1 print ’自增列’ else print ’不是自增列’ 判断表中是否存在索引 if exists(select...
if exists(select * from syscolumns where id=object_id(’表名’) and name=’列名’) alter table 表名 drop column 列名 if exists(select * from syscolumns where id=object_id(’表名’) and name=’列名’) alter table 表名 drop column 列名 9 判断列是否自增列 Sql代码 if columnproperty(obje...
In this post, I am sharing two options for checking whether a column exists in a SQL Server table or not. When you are preparing the full database change script, you should put DDL statements in the IF EXISTS condition for avoiding any error. ...
if exists (select * fromsysobjectswhere id = object_id(N’[表名]’) andOBJECTPROPERTY(id, N’IsUserTable’) = 1) drop table [表名] if exists (select * from sysobjects where id = object_id(N’[表名]’) and OBJECTPROPERTY(id, N’IsUserTable’) = 1) drop table [表名] 3 判断...
alter table 表名 drop column 列名 判断列是否⾃增列 if columnproperty(object_id(’table’),’col’,’IsIdentity’)=1 print ’⾃增列’else print ’不是⾃增列’判断表中是否存在索引 if exists(select * from sysindexes where id=object_id(’表名’) and name=’索引名’)print ’存在’else...
WHERE EXISTS (SELECT column1 FROM table_name2 WHERE condition); DELETE FROM table_name WHERE EXISTS (SELECT column1 FROM table_name2 WHERE condition); ``` 3. 存在性检查:exists可以用于检查一些表中是否存在满足特定条件的记录。 ``` IF EXISTS (SELECT * FROM table_name WHERE condition) BEGIN ...
字段if exists(select * from syscolumns whereid=object_id('table1') andname='name') beginselect * from people;end判断table1中是否存在name字段且删除字段if exists(select * from syscolumns whereid=object_id('table1') andname='name') beginselect * from people;alter table table1 DROP COLUMN ...
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drop table [表名] if exists (select * from sysobjects where id = object_id(N’[表名]’) and OBJECTPROPERTY(id, N’IsUserTable’) = 1) drop table [表名] 3 判断存储过程是否存在 Sql代码 if exists (select * from sysobjects where id = object_id(N’[存储过程名]’) and OBJECTPROPERTY...
#一、IF EXISTS集合语句的语法 IF EXISTS集合语句的语法如下: IF EXISTS (SELECT column_name(s) FROM table_nameWHERE condition) BEGIN 执行操作1 END ELSE BEGIN 执行操作2 END; 其中,`SELECT column_name(s) FROM table_name WHERE condition`是一个SQL查询语句,用于判断条件是否存在。如果该查询返回至少一行...