How to Drop Unique Constraint in Laravel Migration?

Hi Folks,

In this article, we will cover how to drop unique constraint in laravel migration. I explained simply step by step laravel migration drop unique constraint. you can understand a concept of laravel migration drop unique. This example will help you laravel migration remove unique. you will do the following things for laravel migration remove unique constraint.

The Laravel migration provides the unique() method to add a SQL unique constraint. Once you have added the unique constraint, you can also drop it. Here is a simple example of how to drop a unique constraint in Laravel migration using the dropUnique() method.

You will see the following examples:

1. Laravel Migration Add Unique Constraint

2. Laravel Migration Drop Unique Constraint

let's see the one by one.

Example 1: Laravel Migration Add Unique Constraint

Here, we will create products table with add Unique Constraint to code column.

Create new migration using following command:

php artisan make:migration create_products_table

Now, You can update it as like the bellow:

database/migrations/migration_name.php

<?php
  
use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Support\Facades\Schema;
  
return new class extends Migration
{
    /**
     * Run the migrations.
     */
    public function up(): void
    {
        Schema::create('products', function (Blueprint $table) {
            $table->id();
            $table->string('name');
            $table->string('code')->unique();
            $table->text('description');
            $table->timestamps();
        });
    }
  
    /**
     * Reverse the migrations.
     */
    public function down(): void
    {
        Schema::dropIfExists('products');
    }
};

Now, you are ready to run migration command:

php artisan migrate

You will see the layout as like the below:

Example 2: Laravel Migration Drop Unique Constraint

Here, we will create products table with drop Unique Constraint to code column.

Create new migration using following command:

php artisan make:migration change_datatype_column

Now, You can update it as like the bellow:

database/migrations/migration_name.php

<?php
  
use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Support\Facades\Schema;
  
return new class extends Migration
{
    /**
     * Run the migrations.
     */
    public function up(): void
    {
        Schema::table('products', function (Blueprint $table) {
            $table->dropUnique('products_code_unique');
        });
    }
  
    /**
     * Reverse the migrations.
     */
    public function down(): void
    {
        Schema::dropIfExists('products');
    }
};

Now, you are ready to run migration command:

php artisan migrate

I hope it can help you...