SQL Reference

TIMESTAMPDIFF

>>-TIMESTAMPDIFF--(--expression--,--expression--)--------------><
 

The schema is SYSFUN.

Returns an estimated number of intervals of the type defined by the first argument, based on the difference between two timestamps.

The first argument can be either INTEGER or SMALLINT. Valid values of interval (the first argument) are:

1

Fractions of a second

2

Seconds

4

Minutes

8

Hours

16

Days

32

Weeks

64

Months

128

Quarters

256

Years

The second argument is the result of subtracting two timestamps types and converting the result to CHAR(22).

The result of the function is INTEGER. The result can be null; if the argument is null, the result is the null value.

The following assumptions may be used in estimating the difference:

• there are 365 days in a year
• there are 30 days in a month
• there are 24 hours in a day
• there are 60 minutes in an hour
• there are 60 seconds in a minute

These assumptions are used when converting the information in the second argument, which is a timestamp duration, to the interval type specified in the first argument. The returned estimate may vary by a number of days. For example, if the number of days (interval 16) is requested for a difference in timestamps for '1997-03-01-00.00.00' and '1997-02-01-00.00.00', the result is 30. This is because the difference between the timestamps is 1 month so the assumption of 30 days in a month applies.