IF ELSE condition on ORACLE

Question

I'm trying to make a sql request on Oracle but i'hve a little probleme. I've this sentence to translate and I don't know how.. Can you help me ? How can I translate it ? :(

IF(CODE="fuu")
THEN(SELECT bar FROM TABLE)
ELSE(we return 0)

Thx in advice.

EDIT :

My request is like that

SELECT distinct
  A, B, C, D, E,
  SUM(F+G+H) AS "FGH",
  SUM(I -(FGH)) AS "I",
  CASE WHEN code='fuu' THEN bar ELSE 0 END AS AS "What I need"
FROM
  TABLE
WHERE 
  A=20
GROUP BY
  A, B, C, D, E;

This solution works but i'don't have the good answer for it. Actually is should have for A=20 -> bar = 7598 and not 0;

Answer 1

A case expression in SQL is an equivalent to IF statement in other languages:

CASE WHEN condition THEN value1 [ ELSE value2 ] END

I guess that you are looking for something like this:

SELECT distinct
  A, B, C, D, E,
  SUM(F+G+H) AS "FGH",
  SUM(I -(FGH)) AS "I",
  CASE WHEN CODE='fuu' THEN bar ELSE 0 END As "What I need"
FROM
  TABLE
WHERE 
  A=20
GROUP BY
  A, B, C,  D, E, "What I need"