如何截断外键约束表？

问题：

Why doesn't a TRUNCATE on mygroup work? 为什么mygroup上的TRUNCATE不起作用？ Even though I have ON DELETE CASCADE SET I get: 即使我有ON DELETE CASCADE SET我得到：

ERROR 1701 (42000): Cannot truncate a table referenced in a foreign key constraint ( mytest . instance , CONSTRAINT instance_ibfk_1 FOREIGN KEY ( GroupID ) REFERENCES mytest . mygroup ( ID )) ERROR 1701（42000）：无法截断外键约束引用的表（ mytest 。 instance ，约束instance_ibfk_1外键（ GroupID ）参考文献mytest 。 mygroup （ ID ））

drop database mytest;
create database mytest;
use mytest;

CREATE TABLE mygroup (
   ID    INT NOT NULL AUTO_INCREMENT PRIMARY KEY
) ENGINE=InnoDB;

CREATE TABLE instance (
   ID           INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
   GroupID      INT NOT NULL,
   DateTime     DATETIME DEFAULT NULL,

   FOREIGN KEY  (GroupID) REFERENCES mygroup(ID) ON DELETE CASCADE,
   UNIQUE(GroupID)
) ENGINE=InnoDB;

---

解决方案：

参考一： https://stackoom.com/question/MsVk/如何截断外键约束表
参考二： https://oldbug.net/q/MsVk/How-to-truncate-a-foreign-key-constrained-table

来源：oschina

链接：https://my.oschina.net/stackoom/blog/4278894