mysql删除有外链索引数据,Cannot delete or update a parent row: a foreign key constraint fails 问题的解决办法 该条记录的某个字段作为innodb的另外一个表的外链。而在删除操作时会自动检查外链。 解决办法一:先判断删除关联数据,然后再删除(这样比较符合业务逻辑比较安全)。 解决办法二:不检查外链,设置FOREIGN_...
Cannot delete or update a parent row: a foreign key constraint fails 问题的解决办法 查询:DELETE FROM `goods` WHERE `goods_id` = '11' 错误代码: 1451 Cannot delete or update a parent row: a foreign key constraint fails (`webDB`.`goods_properties_detail`, CONSTRAINT `FK_rip_43` FOREIGN ...
报错信息如下: (pymysql.err.IntegrityError) (1452, u'Cannot add or update a child row: a foreign key constraint fails 解决办法: SET FOREIGN_KEY_CHECKS = 0; # 临时取消外键约束 SET FOREIGN_KEY_CHECKS = 1; # 开启外键约束 添加之前临时取消一下外键约束,添加好数据之后,再将外键约束改回来就可以...
The FOREIGN KEY constraint is used to prevent actions that would destroy links between tables.A FOREIGN KEY is a field (or collection of fields) in one table, that refers to the PRIMARY KEY in another table.The table with the foreign key is called the child table, and the table with ...
ERROR 1217 (23000): Cannot delete or update a parent row: a foreign key constraint fails 原因 可能是在Mysql中,删除的表和另一张表设置了foreign key的关联,造成无法更新或删除数据; 解决方案 可以通过设置FOREIGN_KEY_CHECKS变量来避免这种情况。
show create table tscore; 系统显示类似如下。 执行如下SQL语句,为tstudent表添加主键。 alter table tstudent add primary key(sno); 执行如下SQL语句,创建外键约束即可成功。 alter table tscore add constraint fk_tscore_sno foreign key(sno) references tstudent(sno);Copyright...
id INT PRIMARY KEY, name VARCHAR(22), deptId INT, CONSTRAINT fk_emp_dept1 FOREIGN KEY(deptId) REFERENCES t_dept(deptId) );实际操作如图:添加常用约束在数据库的使用过程中我们经常要限制字段的取值,比如有些字我们不能让它为空,我们就需要添加非空约束。怎么...
接下来我们需要关联product.sid 至 sealer.id,进行父子表的主外键关联。 2. 碰到错误 在创建外键之时,使用的SQL和碰到错误信息如下: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 alter table`product' add CONSTRAINT`sid_ref`FOREIGN KEY (`sid`) REFERENCES`sealer`(`id`)ONDELETENOACTIONONUPDATENOAC...
[Err] 1701 -Cannot truncate a table referenced in a foreign key constraint … 解决办法 删除之前先执行删除外键约束 代码语言:javascript 代码运行次数:0 SETforeign_key_checks=0; 删除完之后再执行启动外键约束 代码语言:javascript 代码运行次数:0
Creating a foreign key constraint requires theREFERENCESprivilege on the parent table. Corresponding columns in the foreign key and the referenced key must have similar data types.The size and sign of fixed precision types such asINTEGERandDECIMALmust be the same. The length of string types need ...