how do we make reference out of two tables? mysql
this is my tables
CREATE TABLE IF NOT EXISTS `carslibrary` (
`CarID` int(10) unsigned NOT NULL AUTO_INCREMENT,
`CarName` varchar(255) NOT NULL,
PRIMARY KEY (`CarID`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 AUTO_INCREMENT=12 ;
CREATE TABLE IF NOT EXISTS `colorslibrary` (
`ColorID` int(11) unsigned NOT NULL AUTO_INCREMENT,
`ColorName` varchar(255) NOT NULL,
PRIMARY KEY (`ColorID`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 AUTO_INCREMENT=7 ;
i want to create another table with reference to CarID and ColorID
i made a table named facerecord
CREATE TABLE IF NOT EXISTS `facerecord` (
`carslibrary_ID` int(10) NOT NULL,
`colorslibrary_ID` int(11) NOT NULL,
KEY `carslibrary_ID` (`carslibrary_ID`),
KEY `colorslibrary_ID` (`colorslibrary_ID`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
i am getting this error
Error creating foreign key on carslibrary_ID (check data types)
Error creating foreign key on colorslibrary_ID (check data types)
Error
ALTER TABLE `facerecord` ADD FOREIGN KEY ( `carslibrary_ID` ) REFERENCES `cars2`.`carslibrary` 开发者_JAVA百科(
`CarID`
) ON DELETE SET NULL ON UPDATE SET NULL ;
ALTER TABLE `facerecord` ADD FOREIGN KEY ( `colorslibrary_ID` ) REFERENCES `cars2`.`colorslibrary` (
`ColorID`
) ON DELETE SET NULL ON UPDATE SET NULL ;
You have mismatched data types in that your main tables use unsigned
integer types, but your facerecord
table uses plain signed INT(10), INT(11)
as the data types.
Change facerecord
to:
CREATE TABLE IF NOT EXISTS `facerecord` (
`carslibrary_ID` int(10) unsigned NOT NULL,
`colorslibrary_ID` int(11) unsigned NOT NULL,
KEY `carslibrary_ID` (`carslibrary_ID`),
KEY `colorslibrary_ID` (`colorslibrary_ID`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
CarId
and ColorId
are unsigned integers, so you should use:
CREATE TABLE IF NOT EXISTS `facerecord` (
`carslibrary_ID` int(10) unsigned NOT NULL,
`colorslibrary_ID` int(11) unsigned NOT NULL,
KEY `carslibrary_ID` (`carslibrary_ID`),
KEY `colorslibrary_ID` (`colorslibrary_ID`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
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