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Development Tools Database Foundations Joining Relational Data Between Tables in SQL Keys and Auto-Incrementing Values

Mayur Pande
PLUS
Mayur Pande
Courses Plus Student 11,711 Points

Getting error code 1005

When trying to create a table with a constraint and foreign key, I keep getting the error message

Error Code: 1005. Can't create table 'londontutors.driver' (errno: 150) 0.074 sec

here are my tables previously

CREATE TABLE `user` (
  `email` varchar(80) NOT NULL,
  `password` varchar(80) NOT NULL,
  `name` varchar(100) NOT NULL,
  `address` varchar(200) NOT NULL,
  `phone` varchar(50) NOT NULL,
  `type` varchar(50) NOT NULL,
  PRIMARY KEY (`email`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

CREATE TABLE `grouptuition` (
  `tutoremail` varchar(80) NOT NULL,
  `starttime` datetime NOT NULL,
  `endtime` datetime NOT NULL,
  `location` varchar(80) NOT NULL,
  `class` varchar(80) NOT NULL,
  `level` varchar(80) NOT NULL,
  `topic` varchar(200) NOT NULL,
  `capacity` int(11) NOT NULL,
  PRIMARY KEY (`tutoremail`,`starttime`),
  CONSTRAINT `grouptuition_ibfk_1` FOREIGN KEY (`tutoremail`) REFERENCES `user` (`email`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

CREATE TABLE `tutor` (
  `email` varchar(80) NOT NULL,
  `username` varchar(80) NOT NULL,
  `subjects` text NOT NULL,
  `summary` text NOT NULL,
  `about` text NOT NULL,
  `image` varchar(200) NOT NULL,
  PRIMARY KEY (`username`),
  UNIQUE KEY `username` (`username`),
  KEY `email` (`email`),
  CONSTRAINT `tutor_ibfk_1` FOREIGN KEY (`email`) REFERENCES `user` (`email`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

and this is the table I am trying to create

create table `driver`(
    `driveremail` VARCHAR(80) NOT NULL,
    `tutoremail` VARCHAR(80) NOT NULL,
    `starttime` DATETIME NOT NULL,
    `location` VARCHAR(80) NOT NULL,
    `class` VARCHAR(80) NOT NULL,
    `topic` VARCHAR(200) NOT NULL,
    PRIMARY KEY (`driveremail`),
    CONSTRAINT `driver_ibfk_1` FOREIGN KEY (`driveremail`) REFERENCES `tutor` (`email`),
    CONSTRAINT `driver_ibfk_2` FOREIGN KEY (`tutoremail`,`starttime`,`location`,`class`,`topic`) references `grouptuition` (`tutoremail`,`starttime`,`location`,`class`,`topic`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
Mayur Pande
Mayur Pande
Courses Plus Student 11,711 Points

solved it, didn't realise that I with foreign keys you can only reference primary keys of the parent table.