Do something on a Record if it not updated for sometime

Question

I'm in need of answer for the below. Kindly help
I would like to perform some operation on a record, if it not updated / modified for more than 30 seconds. How can we achieve this in Oracle ?

Answer 1

Hi,
You should have a column in the table called last modified date,
which will be updated using a trigger that updates the column with sysdate when ever it is updated.
See the follwoing
SQL> CREATE TABLE TEST
  2  (
  3     ID             NUMBER
  4    ,LAST_MODIFIED_DATE DATE
  5  );
Table created.
SQL>
SQL> CREATE OR REPLACE TRIGGER TRG_TEST_UPDATE
  2     BEFORE INSERT
  3     ON TEST
  4     FOR EACH ROW
  5  BEGIN
  6     :NEW.LAST_MODIFIED_DATE := SYSDATE;
  7  END;
  8  /
Trigger created.
SQL>
SQL> INSERT INTO TEST (ID)
  2       VALUES (1);
1 row created.
SQL>     
SQL> SELECT * FROM TEST;
        ID LAST_MODI
         1 08-MAR-11
--After 30 seconds.
SQL>     
SQL> SELECT *
  2    FROM TEST
  3   WHERE (SYSDATE - LAST_MODIFIED_DATE) * 24 * 3600 > 30;
        ID LAST_MODI
         1 08-MAR-11
SQL> G.