Laravel Schema onDelete set null

Question

Can't figure out how to set the proper onDelete constraint on a table in Laravel. (I'm working with SQLite)

$table->...->onDelete('cascade'); // works
$table->...->onDelete('null || set null'); // neither of them work

I have 3 migrations, creating the gallery table:

Schema::create('galleries', function($table)
{
    $table->increments('id');
    $table->string('name')->unique();
    $table->text('path')->unique();
    $table->text('description')->nullable();
    $table->timestamps();
    $table->engine = 'InnoDB';
});

Creating the pictures table:

Schema::create('pictures', function($table)
{
    $table->increments('id');
    $table->text('path');
    $table->string('title')->nullable();
    $table->text('description')->nullable();
    $table->integer('gallery_id')->unsigned();
    $table->foreign('gallery_id')
        ->references('id')->on('galleries')
        ->onDelete('cascade');
    $table->timestamps();
    $table->engine = 'InnoDB';
});

Linking gallery table to a picture:

Schema::table('galleries', function($table)
{
    // id of a picture that is used as cover for a gallery
    $table->integer('picture_id')->after('description')
        ->unsigned()->nullable();
    $table->foreign('picture_id')
        ->references('id')->on('pictures')
        ->onDelete('cascade || set null || null'); // neither of them works
});

I do not receive any errors. Also, even the "cascade" option doesn't work (only on the gallery table). Deleting a gallery deletes all pictures. But deleting the cover picture, wont delete the gallery (for test purposes).

Since even the "cascade" is not triggered, I "set null" is not the problem.

EDIT (workaround):

After reading this article I've changed my schema a bit. Now, the pictures table contains an "is_cover" cell, that indicates whether this picture is a cover on its album or not.

A solution to the original problem is still highly appreciated!

Answer 1

If you want to set null on delete:

$table->...->onDelete('set null');

First make sure you set the foreign key field as nullable:

$table->integer('foreign_id')->unsigned()->nullable();

Answer 2

According to

http://dev.mysql.com/doc/refman/5.6/en/innodb-foreign-key-constraints.html

$table->onDelete('set null') should work prehaps try

$table->...->onDelete(DB::raw('set null'));

If there are any errors, would also be helpful

Answer 3

• This is a known issue in Laravel. More info about this here.

• This feature is not supported in SQLite, see here

• Also a topic that has a detailed showdown of this problem

Answer 4

In laravel 7 and 8 you can use:

$table->foreignId('foreign_id')->nullable()->constrained("table_name")->cascadeOnUpdate()->nullOnDelete();

Reference

The different options are declared in the class Illuminate\Database\Schema\ForeignKeyDefinition (see source).

Answer 5

SQLite doesn't support the ADD CONSTRAINT variant of the ALTER TABLE command

SQLite foreign key dont set null on delete in phpunit test

Answer 6

Using Laravel 4.2 on MySQL 5.5 with InnoDB, onDelete('set null') works.

Answer 7

in laravel 8 you can do it like this.

 $table->foreignId('table_id')->nullable()->constrained()->onDelete('set null');

nullable() column modifiers must be called before constrained() and onDelete('set null')

Answer 8

you can use nullOnDelete() method as well. See laravel 8.x https://laravel.com/docs/8.x/migrations#foreign-key-constraints

$table->foreignId('table_id')->nullable()->constrained()->nullOnDelete();