PRINT'exists' altertable表名dropconstraint默认值名称 go altertable表名dropcolumn列名 go ----- --判断要创建临时表是否存在 If Object_Id('Tempdb.dbo.#Test')IsNotNull Begin print'存在' End Else Begin print'不存在' End --------------- --
);IF@ConstraintNameISNOTNULLBEGINEXEC('ALTER TABLE __TableName__ DROP CONSTRAINT'+@ConstraintName);END 另一方法(修改字段类型) IFEXISTS(SELECTnameFROMSYSOBJECTSWHEREname='__TableName__'ANDxtype='U')BEGINDECLARE@nameVARCHAR(100)=(SELECTTOP1nameFROMSYSOBJECTSWHEREnameLIKE'DF\_\_%'ESCAPE'\'ANDx...
drop proc usp_getAllStuInfo go create procedure usp_getAllStuInfo as select * from Student go --调用存储过程,获取的有学员信息 execute usp_getAllStuInfo --exec sp_executesql 'select * from Student' --查询指定性别的学员信息 go if exists(select * from sysobjects where name='usp_getAllStuI...
在 SQL Server 中,这个性能由 timestamp 数据类型提供,它是一个二进制数字,表示数据库中更改的相对顺序。每个数据库都有一个全局当前时间戳值:@@DBTS。每次以任何方式更改带有 timestamp 列的行时,SQL Server 先在时间戳列中存储当前的 @@DBTS 值,然后增加 @@DBTS 的值。如果某 个表具有 timestamp 列,则...
mysql 连接 mssql MySQL 连接串 支持别名 一、了解MySQL 1、什么是数据库? 数据库是一种以某种有组织的方式存储的数据集合。 2、模式(schema):关于数据库和表的布局及特性的信息。 3、列:正确的将数据分解为多个列极为重要。通过把它分解开,才有可能利用特定的列对数据进行排序和过滤。
Subclause 11.26, "<drop table constraint definition>": <drop table constraint definition> ::= DROP CONSTRAINT <constraint name> <drop behavior> ... Conformance Rules Without Feature F381, "Extended schema manipulation", conforming SQL language shall not contain a <drop table constraint definit...
If not, what is the expected SQL? Copy link chris-digitise commented Nov 3, 2021 To fix this, the appropriate script would be ALTER TABLE dbo.MyTable DROP CONSTRAINT CHK_randomname then ALTER TABLE dbo.MyTable WITH NOCHECK ADD CONSTRAINT CHK_randomname CHECK add_the_check_condition_here...
(select1fromsys.objectswherename=N'DBAReadLog')dropfunctiondbo.DBAReadLogif exists(select1fromsys.assemblieswherename=N'FCLR') drop assembly FCLR create assembly FCLRfrom'D:\MSSQLLogAnalyzer\FCLR\bin\Debug\FCLR.dll'with permission_set=unsafe alter assembly FCLR add filefrom'D:\MSSQL...
Violation of PRIMARY KEY constraint 'PK_test'. Cannot insert duplicate key in object 'dbo.test'. The duplicate key value is (12610). (Source: MSSQLServer, Error number: 2627) ? Thanks, Ram RAM There can be two reasons 1. The insert script used is having multiple instances of the re...
converting constraint from ms sql to mysql Jignesh Patel November 19, 2013 10:10AM Re: converting constraint from ms sql to mysql Vladimir Bilyak January 22, 2014 10:36AM Sorry, you can't reply to this topic. It has been closed....