Description:
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If you execute an empty query the result is an error "Query failed". In earlier versions the result was bool(true).

Reproduce code:
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//After connect

$result = mssql_query(null);
var_dump($result);

/* or */
// $result = mssql_query("");
//var_dump($result);



Expected result:
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var_dump(result) has to return bool(true)

Actual result:
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Query failed.