CREATE OR REPLACE FUNCTION uf_timestamp_diff(endtime in TIMESTAMP,starttime in TIMESTAMP)
RETURN INTEGER
AS
str VARCHAR2(50);
misecond INTEGER;
seconds INTEGER;
minutes INTEGER;
hours INTEGER;
days INTEGER;
BEGIN
str:=to_char(endtime-starttime);
misecond:=to_number(SUBSTR(str,INSTR(str,' ')+10,3));
seconds:=to_number(SUBSTR(str,INSTR(str,' ')+7,2));
minutes:=to_number(SUBSTR(str,INSTR(str,' ')+4,2));
hours:=to_number(SUBSTR(str,INSTR(str,' ')+1,2));
days:=to_number(SUBSTR(str,1,INSTR(str,' ')));
RETURN days*24*60*60*1000+hours*60*60*1000+minutes*60*1000+seconds*1000+misecond;
END;