phplaraveltransactions

Laravel: Using try...catch with DB::transaction()


We all use DB::transaction() for multiple insert queries. In doing so, should a try...catch be placed inside it or wrapping it? Is it even necessary to include a try...catch when a transaction will automatically fail if something goes wrong?

Sample try...catch wrapping a transaction:

// try...catch
try {
    // Transaction
    $exception = DB::transaction(function() {

        // Do your SQL here

    });

    if(is_null($exception)) {
        return true;
    } else {
        throw new Exception;
    }

}
catch(Exception $e) {
    return false;
}

The opposite, a DB::transaction() wrapping a try...catch:

// Transaction
$exception = DB::transaction(function() {
    // try...catch
    try {

        // Do your SQL here

    }
    catch(Exception $e) {
        return $e;
    }

});

return is_null($exception) ? true : false;

Or simply a transaction w/o a try...catch

// Transaction only
$exception = DB::transaction(function() {

    // Do your SQL here

});

return is_null($exception) ? true : false;

Solution

  • In the case you need to manually 'exit' a transaction through code (be it through an exception or simply checking an error state) you shouldn't use DB::transaction() but instead wrap your code in DB::beginTransaction and DB::commit/DB::rollback():

    DB::beginTransaction();
    
    try {
        DB::insert(...);
        DB::insert(...);
        DB::insert(...);
    
        DB::commit();
        // all good
    } catch (\Exception $e) {
        DB::rollback();
        // something went wrong
    }
    

    See the transaction docs.