Selecting dates from friday till sunday???

Question

Hello folks,
Am trying to work on a query where there is a date selection in the where clause. i.e if sysdate is monday i have to get the data from friday until Sunday.
   and sh.change_date >=
               to_date('20110304 000000', 'YYYYMMDD HH24MISS')
           and sh.change_date <=
               to_date('20110306 235959', 'YYYYMMDD HH24MISS')Now am hardcoding the dates that i want to see in the change_date. But Is there any way that every time when i run the query i dont have to change these date values??
Thanks a Bunch!

Answer 1

Please see the following
SQL> SELECT * FROM TEST_A;
        ID COL                                                CHANGE_DA
         1 A                                                  04-MAR-11
         2 A1                                                 03-MAR-11
         3 A1                                                 04-MAR-11
         5 A1                                                 06-MAR-11
         6 A1                                                 05-MAR-11
         7 A1                                                 07-MAR-11
6 rows selected.
--Today is monday so ruuning as of today.
SQL> SELECT *
  2    FROM test_a
  3   WHERE TRUNC (change_date) BETWEEN DECODE (TRIM (TO_CHAR ( SYSDATE, 'DAY')),
  4                                             'MONDAY', TRUNC (SYSDATE) - 3,
  5                                             TRUNC (SYSDATE) - 1)
  6                                 AND TRUNC (SYSDATE) - 1;
        ID COL                                                CHANGE_DA
         1 A                                                  04-MAR-11
         3 A1                                                 04-MAR-11
         5 A1                                                 06-MAR-11
         6 A1                                                 05-MAR-11
--Running as of tomorrow i.e tuesday. So adding 1 to all SYSDATE's
SQL> SELECT *
  2    FROM test_a
  3   WHERE TRUNC (change_date) BETWEEN DECODE (TRIM (TO_CHAR ( SYSDATE+1, 'DAY')),
  4                                             'MONDAY', TRUNC (SYSDATE+1) - 3,
  5                                             TRUNC (SYSDATE+1) - 1)
  6                                 AND TRUNC (SYSDATE+1) - 1;
        ID COL                                                CHANGE_DA
         7 A1                                                 07-MAR-11
SQL> Hope this helps.
G.