BETWEEN 子句可以代替“大于等于XX,并且小于等于XX”這樣的條件。
為了理解 BETWEEN 子句,依舊來(lái)看 employee_tbl 這個(gè)例子,它的所有記錄如下:
mysql> SELECT * FROM employee_tbl;
+------+------+------------+--------------------+
| id | name | work_date | daily_typing_pages |
+------+------+------------+--------------------+
| 1 | John | 2007-01-24 | 250 |
| 2 | Ram | 2007-05-27 | 220 |
| 3 | Jack | 2007-05-06 | 170 |
| 3 | Jack | 2007-04-06 | 100 |
| 4 | Jill | 2007-04-06 | 220 |
| 5 | Zara | 2007-06-06 | 300 |
| 5 | Zara | 2007-02-06 | 350 |
+------+------+------------+--------------------+
7 rows in set (0.00 sec)
假設(shè)要從上表中獲取 daily_typing_pages 大于或等于170,小于或等于300的數(shù)據(jù)??梢岳?>= 與 <= 條件來(lái)實(shí)現(xiàn)。
mysql>SELECT * FROM employee_tbl
->WHERE daily_typing_pages >= 170 AND
->daily_typing_pages <= 300;
+------+------+------------+--------------------+
| id | name | work_date | daily_typing_pages |
+------+------+------------+--------------------+
| 1 | John | 2007-01-24 | 250 |
| 2 | Ram | 2007-05-27 | 220 |
| 3 | Jack | 2007-05-06 | 170 |
| 4 | Jill | 2007-04-06 | 220 |
| 5 | Zara | 2007-06-06 | 300 |
+------+------+------------+--------------------+
5 rows in set (0.03 sec)
用 BETWEEN 實(shí)現(xiàn)起來(lái)就簡(jiǎn)單多了,如下所示:
mysql> SELECT * FROM employee_tbl
-> WHERE daily_typing_pages BETWEEN 170 AND 300;
+------+------+------------+--------------------+
| id | name | work_date | daily_typing_pages |
+------+------+------------+--------------------+
| 1 | John | 2007-01-24 | 250 |
| 2 | Ram | 2007-05-27 | 220 |
| 3 | Jack | 2007-05-06 | 170 |
| 4 | Jill | 2007-04-06 | 220 |
| 5 | Zara | 2007-06-06 | 300 |
+------+------+------------+--------------------+
5 rows in set (0.03 sec)