Submitted by: eXandr (i.reg) Votes: 4 It should be possible to determine not cause an error when deleting an object that does not exist Something like that: execute statement 'ALTER TABLE SOME_TABLE DROP [IF EXISTS] SOME_FIELD'; -- no ra...
DROPTABLEIFEXISTS`courses`; CREATETABLE`courses` ( `courseno`varchar(20)NOTNULL, `coursenm`varchar(100)NOTNULL, PRIMARYKEY (`courseno`) )ENGINE=InnoDBDEFAULTCHARSET=utf8COMMENT='课程表'; -- --- -- Records of courses -- --- INSERTINTO`courses`VALUES ('C001','大学语文'); INSERTINTO`c...
使用SQL语句创建数据库 exist语句用来判断将要建立的数据库是否存在, 如果存在,DROP语句是如果存在,则先删除,然后新建. ***/ use master go if exists (select * from sysdatabases where name ='stuDB') drop database stuDB create datab 1. 2. 3. 4. 5. 6. ase stuDB go 执行语句结果是: 可以看...
drop function [dbo].[函数名] -- 判断要创建的函数名是否存在 if exists (select * from dbo.sysobjects where id = object_id(N’[dbo].[函数名]’) and xtype in (N’FN’, N’IF’, N’TF’)) drop function [dbo].[函数名] 7 获取用户创建的对象信息 Sql代码 SELECT [name],[id],crdat...
execute immediate 'drop table continent'; exception when others then null; end; 这个脚本很适合我。我也使用这个脚本: declare c int; begin select count(*) into c from user_tables where table_name = upper('continent'); if c = 1 then ...
I don't like these, and if you also don't like them, then you might try new DROP IF EXISTS (a.k.a. DIE :) ) statements in SQL Server 2016.From SQL Server 2016 CTP3 you can use new DIE statements instead of big IF wrappers, e.g.:...
EN我已经研究了在SQL Server 2016中删除数据库项时如何测试表或约束的存在，并了解到可以使用'if exist...
一.查看DROP帮助信息 mysql>?DROPMany help itemsforyour request exist.Tomake a more specific request, please type'help <item>',where<item>isoneofthe following topics:ALTERTABLEDEALLOCATEPREPAREDROPDATABASEDROPEVENTDROPFUNCTIONDROPFUNCTIONUDFDROPINDEXDROPPROCEDUREDROPRESOURCEGROUPDROPROLEDROPSERVERDROPSPATIAL ...
DROP TRIGGER trProductInsert I don't like these, and if you also don't like them, then you might try new DROP IF EXISTS (a.k.a. DIE :) ) statements in SQL Server 2016. From SQL Server 2016 CTP3 you can use new DIE statements instead of big IF wrappers, e.g.: ...
我在sqlite中使用了语句drop trigger if exist TRIGGER,但是sql server不喜欢if语句。(我猜exist是一个令人不快的词)。我在create trigger语句旁边执行此操作,因为我想删除同名的旧触发器,以便可以用这个新触发器替换它。如何在SQL server中执行此操作? 浏览2提问于2010-05-19得票数 3 回答已采纳 ...