Mega Code Archive
Calculate the last day of the month for the previous, current, and following months relative to a given date
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n would be -1, 0, and 1
mysql>
mysql> CREATE TABLE date_val
-> (
-> d DATE
-> );
Query OK, 0 rows affected (0.01 sec)
mysql>
mysql> INSERT INTO date_val (d) VALUES('1864-02-28');
Query OK, 1 row affected (0.00 sec)
mysql> INSERT INTO date_val (d) VALUES('1900-01-15');
Query OK, 1 row affected (0.00 sec)
mysql> INSERT INTO date_val (d) VALUES('1987-03-05');
Query OK, 1 row affected (0.00 sec)
mysql> INSERT INTO date_val (d) VALUES('1999-12-31');
Query OK, 1 row affected (0.00 sec)
mysql> INSERT INTO date_val (d) VALUES('2000-06-04');
Query OK, 1 row affected (0.00 sec)
mysql>
mysql>
mysql> SELECT d,
-> DATE_SUB(
-> DATE_ADD(DATE_SUB(d,INTERVAL DAYOFMONTH(d)-1 DAY),INTERVAL 0 MONTH),
-> INTERVAL 1 DAY)
-> AS 'last, prev. month',
-> DATE_SUB(
-> DATE_ADD(DATE_SUB(d,INTERVAL DAYOFMONTH(d)-1 DAY),INTERVAL 1 MONTH),
-> INTERVAL 1 DAY)
-> AS 'last, this month',
-> DATE_SUB(
-> DATE_ADD(DATE_SUB(d,INTERVAL DAYOFMONTH(d)-1 DAY),INTERVAL 2 MONTH),
-> INTERVAL 1 DAY)
-> AS 'last, following month'
-> FROM date_val;
+------------+-------------------+------------------+-----------------------+
| d | last, prev. month | last, this month | last, following month |
+------------+-------------------+------------------+-----------------------+
| 1864-02-28 | 1864-01-31 | 1864-02-29 | 1864-03-31 |
| 1900-01-15 | 1899-12-31 | 1900-01-31 | 1900-02-28 |
| 1987-03-05 | 1987-02-28 | 1987-03-31 | 1987-04-30 |
| 1999-12-31 | 1999-11-30 | 1999-12-31 | 2000-01-31 |
| 2000-06-04 | 2000-05-31 | 2000-06-30 | 2000-07-31 |
+------------+-------------------+------------------+-----------------------+
5 rows in set (0.00 sec)
mysql>
mysql> drop table date_val;
Query OK, 0 rows affected (0.00 sec)
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