使用复合键不正确地形成外键约束

Foreign key constraint is incorrectly formed with Composite Keys

我有一个table"theaters"。其中(theater_name,area_name,station)在table"cubelists"中复合key.And我有列(thtr_name,area,stn) table"theaters".

的(theater_name,area_name,station)

这里的问题是列的组合 - table "theaters" 中的 (theater_name,area_name,station) 是唯一的,因为它是复合键。但是每列单独不是唯一的。

那我如何从 table "cubelists" 中引用这些列呢?

Schema::create('theaters', function (Blueprint $table) {

        $table->string('theater_name');
        $table->string('area_name');
        $table->string('station');
        $table->primary(array('theater_name','area_name','station'));
        $table->text('address');
        $table->bigInteger('phno');
        $table->string('contact_person');

    });



  public function up()
    {
    //
    Schema::create('cubelists', function (Blueprint $table) {
        $table->string('mvie_name');
        $table->foreign('mvie_name')->references('movie_name')->on('movies');
        $table->string('thtr_name');

        $table->string('area');

        $table->string('stn');

        $table->foreign(array('thtr_name','area','stn'))-
        >references(array('theater_name','area_name','station'))-
        >on('theaters');
        $table->primary(array('mvie_name','thtr_name','area','stn'));
        $table->string('type');
        $table->string('subtype');
        $table->date('validity');
        $table->string('show');

    });

}

如果我给出上面的代码,我会得到一个错误,因为

Migration table created successfully.


  [Illuminate\Database\QueryException]
  SQLSTATE[HY000]: General error: 1005 Can't create table `boras_cachii`.`#sql-a10_
  112` (errno: 150 "Foreign key constraint is incorrectly formed") (SQL: alter tabl
  e `agreements` add constraint agreements_area_name_foreign foreign key (`area_nam
  e`) references `cubelists` (`area`))



  [PDOException]
  SQLSTATE[HY000]: General error: 1005 Can't create table `boras_cachii`.`#sql-a10_
  112` (errno: 150 "Foreign key constraint is incorrectly formed")

您必须先创建 table,然后再创建外键。

Schema::create('cubelists', function (Blueprint $table) {
        $table->string('mvie_name');
        $table->string('area');
        $table->string('stn');
        $table->primary(array('mvie_name','thtr_name','area','stn'));
        $table->string('type');
        $table->string('subtype');
        $table->date('validity');
        $table->string('show');

           $table->foreign(array('thtr_name','area','stn'))
            ->references(array('theater_name','area_name','station'))
             ->on('theaters');

           $table->foreign('mvie_name')
           ->references('movie_name')
           ->on('movies');


    });

另外 theaters table 必须首先迁移,因为 cubelists 正在引用它。并确保外键列和引用列的类型或长度相同。