I have table test1 and have one column DOJ with timestamp datatype having few records as shown below. Here i need the difference im milliseconds between doj and systimestamp. SELECT DOJ FROM TEST1; DOJ ---------------------------- 21-MAR-14 09.25.34.514526000 21-MAR-14 09.25.34.520345000 22-MAR-14 09.25.34.523144000 22-MAR-14 09.25.34.527770000 23-MAR-14 09.25.34.532482000 23-MAR-14 09.25.34.535603000 24-MAR-14 09.25.34.538556000 24-MAR-14 09.25.34.541729000 SELECT SYSTIMESTAMP FROM DUAL; SYSTIMESTAMP -------------- 24-MAR-14 09.48.10.251556000 +00:00 Can some one please help me with this.