Description:
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When using the MATCHES(cols...) AGAINST (phrase) construct in MySQL using PDO prepared statements and bound parameters, the binding does not recognize the "?" within the AGAINST ().

Reproduce code:
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$pdo= new PDO("mysql:host=localhost;dbname=some_db","some_user","some_pass");
$sql= "SELECT * FROM some_table WHERE MATCH(some_col) AGAINST (?)";
$statement= $pdo->prepare($sql);
$statement->bindValue(1, "some search phrase");
$statement->execute(); // Will error here with "invalid parameter number, no parameters bound"

If you replace the ? in the SQL statement with the string search phrase value, it will work fine.

Expected result:
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Expect to bind the value into the unnamed parameter and execute properly.

Actual result:
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Warning: PDOStatement::execute() [function.PDOStatement-execute]: SQLSTATE[HY093]: Invalid parameter number: no parameters were bound in XXX