Running Query Based on Condition

Question

Hi
I want to run different query based on a condition. I am not able to execute the following query. is this the right way to run different query based on condition?
SELECT * FROM (
CASE WHEN (SELECT COUNT (*) from data1 where ID = 1 AND stype = 'A') > 0 THEN select * from data where ID = 1 AND stype = 'A'
WHEN (SELECT COUNT (*) from data1 where ID = 1 AND stype = 'B') > 0 THEN select * from data where ID = 1 AND stype = 'B'
WHEN (SELECT COUNT (*) from data1 where ID = 1 AND stype = 'C') > 0 THEN select * from data where ID = 1 AND stype = 'C'
END
) as a;
Edited by: user6016744 on 21 Apr, 2011 12:40 AM

Answer 1

This works for us; hope it helps.
CREATE OR REPLACE FUNCTION SCHEMA.GET_STEP_COST (loan_number_in in VARCHAR2, step_code_in in VARCHAR2 default null, ws_in in VARCHAR2 default null )
RETURN VARCHAR2 IS retval  VARCHAR2 (50);
/*passing in loan number and step code you need the cost for, will return the cost*/
BEGIN
    CASE ws_in --depending on workstation in is the table select
    WHEN 'F' THEN
        EXECUTE IMMEDIATE 'SELECT '|| step_code_in ||' FROM CLAIMS_FCL_STEPS WHERE LOAN_NUMBER = '|| loan_number_in ||'' INTO retval;
    WHEN 'R' THEN
       EXECUTE IMMEDIATE 'SELECT '|| step_code_in ||' FROM CLAIMS_RS_STEPS  WHERE LOAN_NUMBER = '|| loan_number_in ||'' INTO retval;
    WHEN 'L' THEN
       EXECUTE IMMEDIATE 'SELECT '|| step_code_in ||' FROM CLAIMS_LM_STEPS  WHERE LOAN_NUMBER = '|| loan_number_in ||'' INTO retval;   
    ELSE
        retval := 0;
    END CASE;
  RETURN retval;
END GET_STEP_COST;
/