#011784: Database: in() expression quotes sub-selects incorrectly for MySQL handler

When using a a sub select with the IN expression of the Database SQL abstraction, one needs to manually switch off quoting of values to make it work.

Instead of

$q = // Some ezcDbMysqlSelectQuery

$qQuestions = $q->subSelect();
$qQuestions->select( 'id' )->from( 'question' )->where( $qQuestions->expr->eq( 'quiz', $qQuestions->bindValue( (int) $quiz->id ) ) );

$q->where(
    $q->expr->in( 'question', $qQuestions )
);

you need to do

$q = // Some ezcDbMysqlSelectQuery

$qQuestions = $q->subSelect();
$qQuestions->select( 'id' )->from( 'question' )->where( $qQuestions->expr->eq( 'quiz', $qQuestions->bindValue( (int) $quiz->id ) ) );

$q->expr->setValuesQuoting( false );
$q->where(
    $q->expr->in( 'question', $qQuestions )
);
$q->expr->setValuesQuoting( true );

to make the sub-select be executed and not be handled like a value. Quoting should be turned off for any sub-selects that are submitted to an expression and I asume this gives errors with almost any other RDBS, too.

Operating System:
PHP Version: (please be specific, like '4.4.3' or '5.1.5')
Database and version:
Browser (and version):

This example shows the incorrectly quoted query.

$q = $db->createSelectQuery();
$q->select( 'somecol' )->from( 'quiz' );

$qQuestions = $q->subSelect();
$qQuestions->select( 'id' )->from( 'question' )->where(
    $qQuestions->expr->eq( 'quiz', $qQuestions->bindValue( 1 ) )
);

$q->where(
    $q->expr->in( 'question', $qQuestions )
);

echo $q->getQuery();