SECOND()

函数说明

返回 time 中秒的值，取值范围为 0 到 59，如果 time 为 NULL 则返回 NULL。

函数语法

1. > SECOND(time)

参数释义

示例

1. drop table if exists t1;
2. create table t1(a datetime, b timestamp);
3. insert into t1 values("2022-07-01", "2011-01-31 12:00:00");
4. insert into t1 values("2011-01-31 12:32:11", "1979-10-22");
5. insert into t1 values(NULL, "2022-08-01 23:10:11");
6. insert into t1 values("2011-01-31", NULL);
7. insert into t1 values("2022-06-01 14:11:09","2022-07-01 00:00:00");
8. insert into t1 values("2022-12-31","2011-01-31 12:00:00");
9. insert into t1 values("2022-06-12","2022-07-01 00:00:00");

11. mysql> select second(a),second(b) from t1;
12. +-----------+-----------+
13. | second(a) | second(b) |
14. +-----------+-----------+
15. |         0 |         0 |
16. |        11 |         0 |
17. |      NULL |        11 |
18. |         0 |      NULL |
19. |         9 |         0 |
20. |         0 |         0 |
21. |         0 |         0 |
22. +-----------+-----------+
23. 7 rows in set (0.01 sec)

25. mysql> select * from t1 where second(a)>=second(b);
26. +---------------------+---------------------+
27. | a                   | b                   |
28. +---------------------+---------------------+
29. | 2022-07-01 00:00:00 | 2011-01-31 12:00:00 |
30. | 2011-01-31 12:32:11 | 1979-10-22 00:00:00 |
31. | 2022-06-01 14:11:09 | 2022-07-01 00:00:00 |
32. | 2022-12-31 00:00:00 | 2011-01-31 12:00:00 |
33. | 2022-06-12 00:00:00 | 2022-07-01 00:00:00 |
34. +---------------------+---------------------+
35. 5 rows in set (0.00 sec)