You can query for a single row using criteria similar to that of the
fetchAll() method.
Example 287. Example of finding a single row by an expression
<?php
$table = new Bugs();
$select = $table->select()->where('bug_status = ?', 'NEW')
->order('bug_id');
$row = $table->fetchRow($select);
This method returns an object of type Zend_Db_Table_Row_Abstract.
If the search criteria you specified match no rows in the database table, then
fetchRow() returns PHP's
NULL value.