Description:
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A named parameter should be able to be included more than once in a query, but bound only once.  Instead, when code like the given is executed, the following error is produced:

Warning: PDOStatement::execute() [function.PDOStatement-execute]: SQLSTATE[HY093]: Invalid parameter number: number of bound variables does not match number of tokens in /home/njm/public_html/test.php on line 7

Reproduce code:
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$db = new PDO('mysql:host=localhost;dbname=test', 'test', 'whatever');
$db->exec('CREATE TABLE foo (a INT, b INT)');
$sth = $db->prepare('INSERT INTO foo (a, b) VALUES (:value, :value)');
$sth->bindParam(':value', 10);
$sth->execute();


Expected result:
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A row inserted into foo where a = b = 10.