MySQL Removing Some Foreign keys(MySQL 删除一些外键)
问题描述
我有一个表,它的主键在其他几个表中使用,并且有几个指向其他表的外键.
I have a table whose primary key is used in several other tables and has several foreign keys to other tables.
CREATE TABLE location (
locationID INT NOT NULL AUTO_INCREMENT PRIMARY KEY
...
) ENGINE = InnoDB;
CREATE TABLE assignment (
assignmentID INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
locationID INT NOT NULL,
FOREIGN KEY locationIDX (locationID) REFERENCES location (locationID)
...
) ENGINE = InnoDB;
CREATE TABLE assignmentStuff (
...
assignmentID INT NOT NULL,
FOREIGN KEY assignmentIDX (assignmentID) REFERENCES assignment (assignmentID)
) ENGINE = InnoDB;
问题是,当我尝试删除其中一个外键列(即 locationIDX)时,它给了我一个错误.
The problem is that when I'm trying to drop one of the foreign key columns (ie locationIDX) it gives me an error.
错误 1025 (HY000):重命名错误"
"ERROR 1025 (HY000): Error on rename"
如何在不出现此错误的情况下删除上面分配表中的列?
How can I drop the column in the assignment table above without getting this error?
推荐答案
如here,似乎外键约束必须被约束名称删除,而不是索引名称.
As explained here, seems the foreign key constraint has to be dropped by constraint name and not the index name.
语法是:
ALTER TABLE footable DROP FOREIGN KEY fooconstraint;
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本文标题为:MySQL 删除一些外键
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