--
-- DATE
--
CREATE TABLE DATE_TBL (f1 date);
INSERT INTO DATE_TBL VALUES ('1957-04-09');
INSERT INTO DATE_TBL VALUES ('1957-06-13');
INSERT INTO DATE_TBL VALUES ('1996-02-28');
INSERT INTO DATE_TBL VALUES ('1996-02-29');
INSERT INTO DATE_TBL VALUES ('1996-03-01');
INSERT INTO DATE_TBL VALUES ('1996-03-02');
INSERT INTO DATE_TBL VALUES ('1997-02-28');
INSERT INTO DATE_TBL VALUES ('1997-02-29');
ERROR:  Bad date external representation '1997-02-29'
INSERT INTO DATE_TBL VALUES ('1997-03-01');
INSERT INTO DATE_TBL VALUES ('1997-03-02');
INSERT INTO DATE_TBL VALUES ('2000-04-01');
INSERT INTO DATE_TBL VALUES ('2000-04-02');
INSERT INTO DATE_TBL VALUES ('2000-04-03');
INSERT INTO DATE_TBL VALUES ('2038-04-08');
INSERT INTO DATE_TBL VALUES ('2039-04-09');
INSERT INTO DATE_TBL VALUES ('2040-04-10');
SELECT f1 AS "Fifteen" FROM DATE_TBL;
  Fifteen   
------------
 04-09-1957
 06-13-1957
 02-28-1996
 02-29-1996
 03-01-1996
 03-02-1996
 02-28-1997
 03-01-1997
 03-02-1997
 04-01-2000
 04-02-2000
 04-03-2000
 04-08-2038
 04-09-2039
 04-10-2040
(15 rows)

SELECT f1 AS "Nine" FROM DATE_TBL WHERE f1 < '2000-01-01';
    Nine    
------------
 04-09-1957
 06-13-1957
 02-28-1996
 02-29-1996
 03-01-1996
 03-02-1996
 02-28-1997
 03-01-1997
 03-02-1997
(9 rows)

SELECT f1 AS "Three" FROM DATE_TBL
  WHERE f1 BETWEEN '2000-01-01' AND '2001-01-01';
   Three    
------------
 04-01-2000
 04-02-2000
 04-03-2000
(3 rows)

--
-- Simple math
-- Leave most of it for the horology tests
--
SELECT f1 - date '2000-01-01' AS "Days From 2K" FROM DATE_TBL;
 Days From 2K 
--------------
       -15607
       -15542
        -1403
        -1402
        -1401
        -1400
        -1037
        -1036
        -1035
           91
           92
           93
        13977
        14343
        14710
(15 rows)

SELECT f1 - date 'epoch' AS "Days From Epoch" FROM DATE_TBL;
 Days From Epoch 
-----------------
           -4650
           -4585
            9554
            9555
            9556
            9557
            9920
            9921
            9922
           11048
           11049
           11050
           24934
           25300
           25667
(15 rows)

SELECT date 'yesterday' - date 'today' AS "One day";
 One day 
---------
      -1
(1 row)

SELECT date 'today' - date 'tomorrow' AS "One day";
 One day 
---------
      -1
(1 row)

SELECT date 'yesterday' - date 'tomorrow' AS "Two days";
 Two days 
----------
       -2
(1 row)

SELECT date 'tomorrow' - date 'today' AS "One day";
 One day 
---------
       1
(1 row)

SELECT date 'today' - date 'yesterday' AS "One day";
 One day 
---------
       1
(1 row)

SELECT date 'tomorrow' - date 'yesterday' AS "Two days";
 Two days 
----------
        2
(1 row)