在mysql中,可以使用“DROP TRIGGER”语句来删除已经定义的触发器,语法格式“DROP TRIGGER [IF EXISTS] [数据库名] 触发器名”;删除一个表的同时,也会自动删除该表上的触发器。 删除触发器 使用DROP TRIGGER 语句可以删除 MySQL 中已经定义的触发器。 语法格式如下:DROP TRIGGER [ IF EXISTS ] [数据库名] 语...
Description: If more than one `DROP TRIGGER IF EXISTS` statements are executed at the same time for the same table, one or more of the statements may return a MySQL error “ERROR 1360 (HY000): Trigger does not exist” instead of succeeding with a warning as usual. Code examination reveals...
drop trigger if exists tr_buyer; delimiter $$ create trigger tr_buyer after update on buyer for each row begin # update seller set money = money + (买家原有的钱 - 买家现在的钱) '买家买东西的钱'; update seller set money = money + (old.money - new.money); end$$ delimiter ; update...
DROP TRIGGER IF EXISTS 触发器名 注意点 外键约束删除不会触发触发器。 课后练习题 复制一张emps表的空表emps_ back, 只有表结构,不包含任何数据 1.创建触发器emps_ insert_trigger, 每当向emps表中添加一条 记录时,同步将这条记录 DELIMITER // CREATE TRIGGER emps_insert_trigger AFTER INSER...
sql server, sybase enterprise...that checks for the existance of our triggers before drop and then creates the new ones. A drop without the check provides an irritating error message that our users will complain to us about. Ah well. Maybe the exists thing will work in the GA release. ...
Drops the object with IF EXISTS option. If object is invalid for drop function will return without exception.
If exists(Select name From sysobjects Where name=’my_trig’and type=’tr’) (整个If语句 1分) Drop trigger my_trig (0.5分) Go (0.5分) Create trigger my_trig (1分) On student (0.5分) For Delete (1分) As (0.5分) Delete From sc (2分) ...
Bug #23703DROP TRIGGER needs an IF EXISTS Submitted:27 Oct 2006 1:20Modified:30 Nov 2006 19:33 Reporter:Hunter PeressEmail Updates: Status:ClosedImpact on me: None Category:MySQL ServerSeverity:S3 (Non-critical) Version:5.0, 5.1OS:Linux (Linux) ...
--你必须拥有相当大的权限才能创建触发器(CREATE TRIGGER),如果你已经是Root用户,那么就足够了。这跟SQL的标准有所不同。 ~~实例~~ example1: 创建表tab1 1 2 3 4 DROPTABLEIF EXISTS tab1; CREATETABLEtab1( tab1_idvarchar(11) ); 创建表tab2 ...
百度试题 题目删除触发器的语句是()。 A.DROPTRIGGERB.DELETETRIGGERC.DROPTRIGGERIFEXISTSD.DELETETRIGGERIFEXISTS相关知识点: 试题来源: 解析 AC 反馈 收藏