Description:
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What is PDO->query('SELECT ...', PDO::FETCH_COLUMN, $colno) supposed to do if you pass an invalid column number in $colno, e.g.:

$stmt = $pdo->query('SELECT only_column FROM test', PDO::FETCH_COLUMN, -1);

My preference would be to make PDO bail about the invalid offset. However, I do not know if this would work with all drivers. So, maybe its even technically not possible to make PDO emit a warning if the requested column is not available.

In any case, I ask to update the manual and tell people about this edge case.


Reproduce code:
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nixnutz@ulflinux:~/php53> sapi/cli/php -r '$pdo=new PDO("sqlite:/tmp/foo.db"); @$pdo->exec("DROP TABLE test"); $pdo->exec("CREATE TABLE test(id INT)"); $pdo->exec("INSERT INTO test(id) VALUES (1)"); var_dump($pdo->query("SELECT id FROM test", PDO::FETCH_COLUMN, -1)->fetchAll());'
array(0) {
}

(Same with MySQL)

Expected result:
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If possible, make PDO bail out when calling query() with invalid column offsets. If that's not possible for technical reasons, please consider having a note about this in the manual.