"Commands out of sync; you can't run this command now" - Caused by mysqli::multi_query

Question

I am running multiple deletes through mysqli::multi_query and it is messing up the next query in line. The following error is being thrown.

Error - SQLSTATE HY000. 
Sql error: Commands out of sync; you can't run this command now

Do I need to somehow clear the multi query so it doesn't mess with my next query? What is the cause of this error?

And this is how I am running my multi query:

function deleteSomeTables($args) {
    $sql = 'delete 1;delete another;';
    if ($database->multi_query($sql)) {
        return true;
    } else {
        return false;
    }
}

I am using a recent version of Xampp on windows 7

Answer 1

Seva's code will most likely fix your issue, if you're using procedural style like me, use this

do {
  if ($result = mysqli_store_result($connect)) {
    mysqli_free_result($result);
  }
} while (mysqli_next_result($connect));