Hello, i have the following problem and i was wondering if you coulde help me. I'll try to describe it as in depth as i can.
I have a FUNCTION in a postgresql database which subtracts two DOUBLE PRECISION FIELDS and returns the result. The problem is that when the result should be zero, the number i get is a number ridiculously close to zero in scientific notation (for example 2.4697823124E-14) but not zero. I know (or at least i think i know) the problem lies within the way postgresql and Java communicate because if a connect through a console to the db and run the function i get the result right (zero) but if i debug the java code i get ther wrong non-zero-but-very-close result
this is the function:
CREATE OR REPLACE FUNCTION getSaldoParticipante(BIGINT) RETURNS DOUBLE PRECISION AS ' DECLARE idParticipante ALIAS FOR $1; result DOUBLE PRECISION; BEGIN
result := 0;
Select (Select CASE WHEN saldo ISNULL then 0 else saldo end FROM (Select sum(PG.saldo) as saldo FROM pagos.pagos PG WHERE PG.saldo > 0 AND PG.participante=idParticipante AND PG.deleted = false) tmp)-(Select CASE WHEN saldo ISNULL then 0 else saldo end FROM (Select sum(DE.saldo) as saldo FROM pagos.deudas DE WHERE DE.deleted = false AND DE.participante=idParticipante) tmp) INTO result;
RETURN result;
END;' LANGUAGE 'plpgsql' CALLED ON NULL INPUT;
this is the Java code where i get the result that should be zero but instead is just very close to zero
//preparo y ejecuto el statement pstmt = prepareStatement (conn, query, params); rs = pstmt.executeQuery();
//itero los registros while (rs.next()) { //the problems appears at the following line result = rs.getDouble("getSaldoParticipante"); } } catch(Exception e){ ...
the only thing that works here is to use rs.getInt instead of rs.getDouble, but that is not good enough since i dont want to truncate the decimal part of the number.
So, a lot of thanks in advance, any help will be greatly appreciated.