Migrations are like version control for your database, allowing your team to modify and share the application’s database schema. Migrations are typically paired with Laravel’s schema builder to build your application’s database schema. If you have ever had to tell a teammate to manually add a column to their local database schema, you’ve faced the problem that database migrations solve.

The Laravel Schema facade provides database agnostic support for creating and manipulating tables across all of Laravel’s supported database systems.

Generating Migrations

To create a migration, use the make:migration Artisan command:

php artisan make:migration create_users_table

The new migration will be placed in your database/migrations directory. Each migration file name contains a timestamp, which allows Laravel to determine the order of the migrations.

Migration stubs may be customized using stub publishing

The --table and --create options may also be used to indicate the name of the table and whether or not the migration will be creating a new table. These options pre-fill the generated migration stub file with the specified table:

php artisan make:migration create_users_table --create=users

php artisan make:migration add_votes_to_users_table --table=users

If you would like to specify a custom output path for the generated migration, you may use the --path option when executing the make:migration command. The given path should be relative to your application’s base path.

Migration Structure

A migration class contains two methods: up and down. The up method is used to add new tables, columns, or indexes to your database, while the down method should reverse the operations performed by the up method.

Within both of these methods you may use the Laravel schema builder to expressively create and modify tables. To learn about all of the methods available on the Schema builder, check out its documentation. For example, the following migration creates a flights table:

<?php

use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Support\Facades\Schema;

class CreateFlightsTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('flights', function (Blueprint $table) {
            $table->id();
            $table->string('name');
            $table->string('airline');
            $table->timestamps();
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::drop('flights');
    }
}

Running Migrations

To run all of your outstanding migrations, execute the migrate Artisan command:

php artisan migrate

If you are using the Homestead virtual machine, you should run this command from within your virtual machine.

Forcing Migrations To Run In Production

Some migration operations are destructive, which means they may cause you to lose data. In order to protect you from running these commands against your production database, you will be prompted for confirmation before the commands are executed. To force the commands to run without a prompt, use the --force flag:

php artisan migrate --force

Rolling Back Migrations

To roll back the latest migration operation, you may use the rollback command. This command rolls back the last “batch” of migrations, which may include multiple migration files:

php artisan migrate:rollback

You may roll back a limited number of migrations by providing the step option to the rollback command. For example, the following command will roll back the last five migrations:

php artisan migrate:rollback --step=5

The migrate:reset command will roll back all of your application’s migrations:

php artisan migrate:reset

Roll Back & Migrate Using A Single Command

The migrate:refresh command will roll back all of your migrations and then execute the migrate command. This command effectively re-creates your entire database:

php artisan migrate:refresh

// Refresh the database and run all database seeds...
php artisan migrate:refresh --seed

You may roll back & re-migrate a limited number of migrations by providing the step option to the refresh command. For example, the following command will roll back & re-migrate the last five migrations:

php artisan migrate:refresh --step=5

Drop All Tables & Migrate

The migrate:fresh command will drop all tables from the database and then execute the migrate command:

php artisan migrate:fresh

php artisan migrate:fresh --seed

Tables

Creating Tables

To create a new database table, use the create method on the Schema facade. The create method accepts two arguments: the first is the name of the table, while the second is a Closure which receives a Blueprint object that may be used to define the new table:

Schema::create('users', function (Blueprint $table) {
    $table->id();
});

When creating the table, you may use any of the schema builder’s column methods to define the table’s columns.

Checking For Table / Column Existence

You may check for the existence of a table or column using the hasTable and hasColumn methods:

if (Schema::hasTable('users')) {
    //
}

if (Schema::hasColumn('users', 'email')) {
    //
}

Database Connection & Table Options

If you want to perform a schema operation on a database connection that is not your default connection, use the connection method:

Schema::connection('foo')->create('users', function (Blueprint $table) {
    $table->id();
});

You may use the following commands on the schema builder to define the table’s options:

Command	Description
$table->engine = 'InnoDB';	Specify the table storage engine (MySQL).
$table->charset = 'utf8';	Specify a default character set for the table (MySQL).
$table->collation = 'utf8_unicode_ci';	Specify a default collation for the table (MySQL).
$table->temporary();	Create a temporary table (except SQL Server).

Renaming / Dropping Tables

To rename an existing database table, use the rename method:

Schema::rename($from, $to);

To drop an existing table, you may use the drop or dropIfExists methods:

Schema::drop('users');

Schema::dropIfExists('users');

Renaming Tables With Foreign Keys

Before renaming a table, you should verify that any foreign key constraints on the table have an explicit name in your migration files instead of letting Laravel assign a convention based name. Otherwise, the foreign key constraint name will refer to the old table name.

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