Time comparison in database

Question

I'm developing a attendance record for my company and I have the following issues.
The table looks like this.
Table name: Attendance,
Structure is like this,
staffID      int(11)      
date      date
time_in time
time_out time
Date      Time In Time Out
2006-10-05     09:31:00     18:29:00
2006-10-06     09:41:00     16:39:00
Number of late: 2
Total late seconds: 187200
As I would like to compare the time_in against 09:30:00 and get a sum of the amount.
MySQL statement is like this,
SELECT * FROM attendance where staffid = '" . $staffid . "' AND time_in > '09:30:00'
However the return time is 187200. I wonder how they calculate this and if the sql statement is the correct one.

Answer 1

OK, I've modified customer average function found here,
http://www.oracle.com/technology/oramag/oracle/06-jul/o46sql.html
CREATE OR REPLACE TYPE SumInterval
AS OBJECT (
runningSum INTERVAL DAY(9) TO SECOND(9),
STATIC FUNCTION ODCIAggregateInitialize
  ( actx IN OUT SumInterval
  ) RETURN NUMBER,
MEMBER FUNCTION ODCIAggregateIterate
  ( self  IN OUT SumInterval,
    val   IN     DSINTERVAL_UNCONSTRAINED
  ) RETURN NUMBER,
MEMBER FUNCTION ODCIAggregateTerminate
  ( self         IN  SumInterval,
    returnValue  OUT DSINTERVAL_UNCONSTRAINED,
    flags        IN  NUMBER
  ) RETURN NUMBER,
MEMBER FUNCTION ODCIAggregateMerge
  (self IN OUT SumInterval,
   ctx2 IN     SumInterval
  ) RETURN NUMBER,
MEMBER FUNCTION ODCIAggregateDelete
  ( self  IN OUT SumInterval,
    val   IN     DSINTERVAL_UNCONSTRAINED
  ) RETURN NUMBER  
CREATE OR REPLACE TYPE BODY SumInterval AS
STATIC FUNCTION ODCIAggregateInitialize
  ( actx IN OUT SumInterval
  ) RETURN NUMBER IS
  BEGIN
    IF actx IS NULL THEN
      dbms_output.put_line('NULL INIT');
      actx := SumInterval (INTERVAL '0 0:0:0.0' DAY TO SECOND);
    ELSE
      dbms_output.put_line('NON-NULL INIT');
      actx.runningSum := INTERVAL '0 0:0:0.0' DAY TO SECOND;
    END IF;
    RETURN ODCIConst.Success;
  END;
MEMBER FUNCTION ODCIAggregateIterate
  ( self  IN OUT SumInterval,
    val   IN     DSINTERVAL_UNCONSTRAINED
  ) RETURN NUMBER IS
  BEGIN
    DBMS_OUTPUT.PUT_LINE('Iterate ' || TO_CHAR(val));
    IF val IS NULL THEN
        /* Will never happen */
        DBMS_OUTPUT.PUT_LINE('Null on iterate');
    END IF;
    self.runningSum := self.runningSum + val;
    RETURN ODCIConst.Success;
  END;
MEMBER FUNCTION ODCIAggregateTerminate
  ( self        IN  SumInterval,
    ReturnValue OUT DSINTERVAL_UNCONSTRAINED,
    flags       IN  NUMBER
  ) RETURN NUMBER IS
  BEGIN
    dbms_output.put_line('Terminate ' || to_char(flags) || to_char(self.runningsum));
    returnValue := self.runningSum;
    RETURN ODCIConst.Success;
  END;
MEMBER FUNCTION ODCIAggregateMerge
  (self IN OUT SumInterval,
   ctx2 IN     SumInterval
  ) RETURN NUMBER IS
  BEGIN
    self.runningSum := self.runningSum + ctx2.runningSum;
    RETURN ODCIConst.Success;
  END;
MEMBER FUNCTION ODCIAggregateDelete
  ( self  IN OUT SumInterval,
    val   IN     DSINTERVAL_UNCONSTRAINED
  ) RETURN NUMBER IS
  BEGIN
    DBMS_OUTPUT.PUT_LINE('Delete ' || TO_CHAR(val));
    IF val IS NULL THEN
        /* Will never happen */
        DBMS_OUTPUT.PUT_LINE('Null on delete');
    END IF;
    self.runningSum := self.runningSum - val;
    RETURN ODCIConst.Success;
  END;
END;
/* create the aggregate interface function*/
CREATE OR REPLACE FUNCTION sum_interval
  ( x DSINTERVAL_UNCONSTRAINED
  ) RETURN DSINTERVAL_UNCONSTRAINED
    PARALLEL_ENABLE
    AGGREGATE USING SumInterval;after running this script you should be able to get result like this,
SQL> select sum_interval(numtodsinterval(time_in-to_date('9:30:00','HH24:MI:SS'),'day')) from att;
SUM_INTERVAL(NUMTODSINTERVAL(TIME_IN-TO_DATE('9:30:00','HH24:MI:SS'),'DAY')
+000000000 00:12:00.000000000Message was edited by:
nurhidayat