Convert DECIMAL value into String

I have a decimal value in the entity. ENTITY NAME : ORDER Amount = Decimal Through OQL, i am trying to execute the qeury SELECT CAST(O.Amount as String) as Total_Amount from ORDER O; For example, Case 1 : Amount = 0.00 - Query returns 0.00000000 Case 2: Amount = 10.00 - Query returns 10.00 How to retrieve 0.00 in the first case.