PHP版本5.3.10删除外键

Question

I am trying to drop a foreign key, and I know I have to drop its constraint before, but I keep geting this error:

#1064 - You have an error in your SQL syntax; check the manual that
corresponds to your MySQL server version for the right syntax to use near
'CONSTRAINT `fk_facility`' at line 2

First I did this :

ALTER TABLE `facilities` 
DROP CONSTRAINT `fk_facility`;

And I aimed to do this secondly:

ALTER TABLE `facilities` 
DROP FOREIGN KEY `building_Id`;

Show create table:

CREATE TABLE `facilities` (
`ID` int(11) NOT NULL AUTO_INCREMENT,
`building_Id` int(11) NOT NULL,
`name` varchar(255) NOT NULL,
`type` varchar(255) DEFAULT NULL,
`area` varchar(255) DEFAULT NULL,
`capacity` varchar(255) DEFAULT NULL,
`quantity` tinyint(4) DEFAULT NULL,
`internet` char(13) DEFAULT NULL,
`availability` char(3) DEFAULT NULL,
`comments` varchar(255) DEFAULT NULL,
PRIMARY KEY (`ID`),
KEY `fk_facility` (`building_Id`),
CONSTRAINT `fk_facility` FOREIGN KEY (`building_Id`) REFERENCES `buildings`
(`ID`) ON DELETE CASCADE) ENGINE=InnoDB AUTO_INCREMENT=30 DEFAULT CHARSET=latin1

Answer 1

To drop a FOREIGN KEY constraint, use the following SQL(MySQL is the odd one out):

MySQL:

ALTER TABLE facilities
DROP FOREIGN KEY fk_facility

SQL Server / Oracle / MS Access:

ALTER TABLE facilities
DROP CONSTRAINT fk_facility