What should I put in my down function when truncate a table in Laravel migration?

Question

I'm trying to write a migration script to truncate my vistors table. We usually place the revert of the up function in the down function.

But in this case, it's a truncate, what should I put in my down function ?

<?php

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

class TruncateVisitorsTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
       DB::table('visitors')->truncate();
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        // what should I put here ? 
    }
}

What you put there depends on what you want? Seed/insert data if there was some fixed data that you truncated from the table.. If it had dynamic data(coming from your application) I wonder why are you truncating it? — codisfy, Mar 25 '16 at 13:32
A true revertible migration would make a backup copy of the table visitors on `up()` before truncating and then copy the backup into the original on `down()`. That may be unnecessary for your needs. — Josh J, Mar 25 '16 at 13:42
@JoshJ is there a way to implement the step you mentioned? Cause i couldn't find any in Laravel docs — Abrar, Jun 16 '20 at 08:19

score 0 · Answer 1 · answered Mar 25 '16 at 16:19

Here is one example I use:

public function up()
{
    Schema::create('users', function(Blueprint $table)
    {
        //
    });

    Schema::create('cats', function(Blueprint $table)
    {
        //
    });

    Schema::create('items', function(Blueprint $table)
    {
        //
    });
}

public function down()
{
    $tables = [
        'users',
        'cats',
        'items'
    ];

    foreach($tables as $table) Schema::drop($table);
}

You would use truncate in the beginning of a seeder.

What should I put in my down function when truncate a table in Laravel migration?

1 Answers1

Linked