php - Can't add Constraint -


i kept getting exception:

[illuminate\database\queryexception]                                            sqlstate[hy000]: general error: 1215 cannot add foreign key constraint (sql     : alter table `messages` add constraint messages_from_foreign foreign key (     `from`) references `id` (`users`))       [pdoexception]                                                             sqlstate[hy000]: general error: 1215 cannot add foreign key constraint

here's createmessagestable class:

public function up()     {         schema::create('messages', function(blueprint $table)         {             $table->bigincrements('id');             $table->biginteger('from', false, true);             ...              $table->foreign('from')->references('users')->on('id');         });     }

and here's createuserstable class:

public function up()     {         // http://laravel.com/docs/5.0/schema         schema::create('users', function(blueprint $table)         {             $table->biginteger('id', true, true);             ...         });     }

i tried double check if had same data type column id in users , from in messages, , were. wonder wrong , why keep getting constraint error messages.

here's problem:

$table->foreign('from')->references('users')->on('id');

the values should other way around - on uses table name , references points column on table.

source: laravel docs


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