Preparing Integers With Doctrine

I recently had an issue with binding an integer to a select statement with doctrine and postgresql.

Given the following:

<?php
    $sql = 'INSERT INTO tree (ancestor, descendant)
            SELECT cta.ancestor, :descendant
            FROM tree AS cta
            WHERE cta.descendant = :ancestor
            UNION ALL
            SELECT :descendant, :descendant';

    $statement = $connection->prepare($sql);
    $statement->bindValue("descendant", (int) $rootNode, 'integer');
    $statement->bindValue("ancestor", (int) $ancestor, 'integer');
    $statement->execute();
?>

I received the following error:

/**
    PHP Fatal error:  Uncaught exception 'PDOException' with message 'SQLSTATE[42P08]: Ambiguous parameter: 7 ERROR:  inconsistent types deduced for parameter $1
    LINE 2:                 SELECT cta.ancestor, $1
                                                          ^
    DETAIL:  integer versus text' in /vagrant_data/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOStatement.php:91
*/

The solution was to explicitly cast it as an integer like so ::integer

And here is the revised code:

<?php
    $sql = 'INSERT INTO tree (ancestor, descendant)
            SELECT cta.ancestor, :descendant::integer
            FROM tree AS cta
            WHERE cta.descendant = :ancestor
            UNION ALL
            SELECT :descendant, :descendant';

    $statement = $connection->prepare($sql);
    $statement->bindValue("descendant", (int) $rootNode, 'integer');
    $statement->bindValue("ancestor", (int) $ancestor, 'integer');
    $statement->execute();
?>

If there are errors or you have a suggestion send me a message @taio.