Truncate MySQL Causes Implicit Commit

Feb 18, 2019 laravel mysql

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I guess I should RTFM more often… but I didn’t remember (or know??) that MySQL truncate table causes an implicit commit.

I was doing unit testing in Laravel using the database transactions trait. Part of my seed data has a dataset. I wanted to get rid of all of that data so I could start fresh in one singular test. So, I started out writing the test like this: MyModel::truncate(). I couldn’t figure out why all of my test data kept getting all messed up then. Turns out, the database transaction can’t protect against implicit commits! Doh!

So, instead, I did this: MyModel::getQuery()->delete(). Then, it was fine with the transactions.

Side note: This article is not me condoning seeding data and then truncating it for unit tests. It just happened to be my circumstance at the time.