Do you know how to decode a date?

Question

HI,I need to count students group by their region on each month. The output is
COUNTRY OCT NOV DEC .....
USA 5 20 30
CAN 100 1 0
MEX 10 20 30
The date format is 5/19/2007
This is my code: and thanks for your help
WITH Q AS (SELECT DISTINCT A.STDID, A.NUMBER, A.ADMIT
               FROM PROG A
                    JOIN CITIZEN B ON A.STDID = B.STDID
                    JOIN REGION_TBL C ON C.REGION = B.REGION                          
                    AND A.NUMBER = 'PS'
                    AND A.ADMIT IN ('2007','2008'))
SELECT J.REGION, I.DESCR,
SUM(DECODE(L.DATE, '9', 1, 0)) SEP_TOTAL,
SUM(DECODE(L.DATE, '10', 1, 0)) OCT_TOTAL,
SUM(DECODE(L.DATE, '11', 1, 0)) NOV_TOTAL,
SUM(DECODE(L.DATE, '12', 1, 0)) DEC_TOTAL,
SUM(DECODE(L.DATE, '1', 1, 0)) JAN_TOTAL,
SUM(DECODE(L.DATE, '2', 1, 0)) FEB_TOTAL
SUM(DECODE(L.DATE, '3', 1, 0)) MAR_TOTAL,
SUM(DECODE(L.DATE, '4', 1, 0)) ARL_TOTAL,
SUM(DECODE(L.DATE, '5', 1, 0)) MAY_TOTAL,
SUM(DECODE(L.DATE, '6', 1, 0)) JUN_TOTAL,
SUM(DECODE(L.DATE, '7', 1, 0)) JUL_TOTAL,
SUM(DECODE(L.DATE, '8', 1, 0)) AUG_TOTAL
FROM CITIZEN J
     JOIN PROG L ON J.STDID = L.STDID
     JOIN Q ON J.STDID = Q.STDID
     AND Q.NUMBER = J.NUMBER
GROUP BY J.REGION, I.DESCR
...

Answer 1

I think you have to take out the 'MM' part of the date to compare in the decode. By the way, PROG.DATE is really a column name? DATE is a reserved word.
SQL> create table sample1(date date)
  2  /
create table sample1(date date)
ERROR at line 1:
ORA-00904: : invalid identifier
SQL> You need to use to_char() to get the month part of the date and then compare it in the DECODE.
Cheers
Sarma.