Oracle报告将数据库时间戳与当前时间戳进行比较

Question

I'm attempting to write a BeforeReport Trigger that checks to see if a user is accessing report data within 120 seconds of creation.

My code is as follows:

function BeforeReport return boolean is

ENTRYDATE TIMESTAMP;
SERVERDATE TIMESTAMP;
DIFFSECONDS NUMBER;
begin

/*Checks to see if user is accessing the data within 120 seconds of creation in database*/
VALIDTIMELENGTH := 120;
SELECT SYS_DATE INTO ENTRYDATE FROM WOS_REPORT_PARAM WHERE SEQUENCE_NUM=UPPER(:SEQUENCENUM) AND PARAMETER='year';
SERVERDATE := CURRENT_TIMESTAMP;
DIFFSECONDS := ((EXTRACT(YEAR FROM ENTRYDATE)- EXTRACT(YEAR FROM SERVERDATE))*31536000) +
             ((EXTRACT(MONTH FROM ENTRYDATE)- EXTRACT(MONTH FROM SERVERDATE))*2592000) +
             ((EXTRACT(DAY FROM ENTRYDATE) - EXTRACT(DAY FROM SERVERDATE))*86400) +
             ((EXTRACT(HOUR FROM ENTRYDATE) - EXTRACT(HOUR FROM SERVERDATE))*3600) +
             ((EXTRACT(MINUTE FROM ENTRYDATE) - EXTRACT(MINUTE FROM SERVERDATE))*60) +
             (EXTRACT(SECOND FROM ENTRYDATE) - EXTRACT(SECOND FROM SERVERDATE));
  IF DIFFSECONDS > VALIDTIMELENGTH THEN RETURN(FALSE);
  ELSE
  return (TRUE);
  END IF;
  END;

The problem is, my code seems to return true regardless of how much time has gone by. Am I not implementing my seconds/minutes code correctly? Oddly enough , I experimented with making both returns (FALSE) and it still proceeded to pass the report! Oracle Reports is so inconsistent that it's infuriating. Any response is greatly appreciated.

Answer 1

If wos_report_param.sys_date is a TIMESTAMP (note that it's rather confusing to name a column sys_date when there is a sysdate function that returns a DATE ), and assuming that wos_report_param.sys_date is a timestamp in the past, your logic can be simplified quite a bit

IF( current_timestamp - entrydate > numtodsinterval( validTimeLength, 'second' ) )
THEN
  RETURN true;
ELSE 
  RETURN false;
END IF;

If my guess is correct and wos_report_param.sys_date is a timestamp in the past, then the diffseconds you are computing will be a negative number which explains why your procedure always returns false . You need to subtract the earlier date from the later date in order to yield a positive rather than a negative interval. Or you could throw an abs around your diffseconds calculation.