make index in exist coulum laravel code example
Example 1: laravel create migration
php artisan make:migration add_votes_to_users_table --table=users
php artisan make:migration create_users_table --create=users
Example 2: laravel dropIndex
Schema::table('geo', function (Blueprint $table) {
$table->dropIndex(['state']); // Drops index 'geo_state_index'
});