how to make foreign key in laravel code example

Example 1: laravel foreign key

Schema::table('posts', function (Blueprint $table) {
    $table->unsignedBigInteger('user_id');

    $table->foreign('user_id')->references('id')->on('users');
});
OR
Schema::table('posts', function (Blueprint $table) {
    $table->foreignId('user_id')->constrained();
});

Example 2: foreign key laravel migration

$table->foreign('column_name')->references('id')->on('table_name')->onDelete('cascade');

Example 3: laravel migration foreign key 5.6

Schema::table('posts', function (Blueprint $table) {
    $table->unsignedInteger('user_id');

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

Example 4: create foreign key laravel migration

Schema::table('posts', function (Blueprint $table) {
    $table->unsignedBigInteger('user_id');

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