$data passed to foreach is wrong

Calling a query that doesn't use all tablecols gives php warnings such as:

Errorcode: E_WARNING [php warning] (2)
Message: Invalid argument supplied for foreach()
File: Record.php
Line: 1151

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$data = empty($data) ? $this->getTable()->find($id, Doctrine_Core::HYDRATE_ARRAY) : $data;
foreach ($data as $field => $value) {
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$data is empty but not an array.