TIMESTAMP_CMP function

Compares the value of two timestamps and returns an integer. If the timestamps are identical, the function returns 0. If the first timestamp is greater, the function returns 1. If the second timestamp is greater, the function returns -1.

Syntax

TIMESTAMP_CMP(timestamp1, timestamp2)

Arguments

Return type

INTEGER

Examples

The following example compares timestamps and shows the results of the comparison.

SELECT TIMESTAMP_CMP('2008-01-24 06:43:29', '2008-01-24 06:43:29'), TIMESTAMP_CMP('2008-01-24 06:43:29', '2008-02-18 02:36:48'), TIMESTAMP_CMP('2008-02-18 02:36:48', '2008-01-24 06:43:29');

timestamp_cmp  | timestamp_cmp | timestamp_cmp 
---------------+---------------+---------------
             0 |            -1 |             1

The following example compares the LISTTIME and SALETIME for a listing. The value for TIMESTAMP_CMP is -1 for all listings because the timestamp for the sale is after the timestamp for the listing.

select listing.listid, listing.listtime,
sales.saletime, timestamp_cmp(listing.listtime, sales.saletime)
from listing, sales
where listing.listid=sales.listid
order by 1, 2, 3, 4
limit 10;

 listid |      listtime       |      saletime       | timestamp_cmp
--------+---------------------+---------------------+---------------
      1 | 2008-01-24 06:43:29 | 2008-02-18 02:36:48 |            -1
      4 | 2008-05-24 01:18:37 | 2008-06-06 05:00:16 |            -1
      5 | 2008-05-17 02:29:11 | 2008-06-06 08:26:17 |            -1
      5 | 2008-05-17 02:29:11 | 2008-06-09 08:38:52 |            -1
      6 | 2008-08-15 02:08:13 | 2008-08-31 09:17:02 |            -1
     10 | 2008-06-17 09:44:54 | 2008-06-26 12:56:06 |            -1
     10 | 2008-06-17 09:44:54 | 2008-07-10 02:12:36 |            -1
     10 | 2008-06-17 09:44:54 | 2008-07-16 11:59:24 |            -1
     10 | 2008-06-17 09:44:54 | 2008-07-22 02:23:17 |            -1
     12 | 2008-07-25 01:45:49 | 2008-08-04 03:06:36 |            -1
(10 rows)

This example shows that TIMESTAMP_CMP returns a 0 for identical timestamps:

select listid, timestamp_cmp(listtime, listtime)
from listing
order by 1 , 2
limit 10;

 listid | timestamp_cmp
--------+---------------
      1 |             0
      2 |             0
      3 |             0
      4 |             0
      5 |             0
      6 |             0
      7 |             0
      8 |             0
      9 |             0
     10 |             0
(10 rows)