# **TIMEDIFF()**

## **Function Description**

`TIMEDIFF()` returns the difference between two `TIME` or `DATETIME` values. The two expressions of the `TIMEDIFF()` function must be parameters of the same type, namely `TIME` or `DATETIME`. The `TIMEDIFF` function returns the result of `expr1 - expr2` expressed as a time value.

## **Function Syntax**

```text
> TIMEDIFF(expr1,expr2)
```

## **Parameter definition**

| Parameters | Description |
| ---- | ---- |
| expr1, expr2 | Required parameters. The expr1 and expr2 expressions need to have the same type. expr1 and expr2 are strings converted to TIME or DATETIME expressions. Returns NULL if expr1 or expr2 is NULL. |

## **Example**

```text
mysql> select timediff("22:22:22", "11:00:00");
+----------------------------------+
| timediff(22:22:22, 11:00:00) |
+----------------------------------+
| 11:22:22.000000 |
+----------------------------------+
1 row in set (0.01 sec)

mysql> select timediff(cast('22:22:22' as time), null);
+-----------------------------------------------------+
| timediff(cast(22:22:22 as time(26)), null) |
+-----------------------------------------------------+
| NULL |
+-----------------------------------------------------+
1 row in set (0.00 sec)

mysql> select timediff(CAST('2017-08-08 22:22:22' as datetime), CAST('2000-01-02 11:00:00' as datetime));
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| timediff(cast(2017-08-08 22:22:22 as datetime(26)), cast(2000-01-02 11:00:00 as datetime(26))) |
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| 154283:22:22 |
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1 row in set (0.00 sec)
```

```text
create table time_01(t1 time,t2 time,t3 time);
insert into time_01 values("-838:59:59.0000","838:59:59.00","22:00:00");
insert into time_01 values("0:00:00.0000","0","0:00");
insert into time_01 values(null,NULL,null);
insert into time_01 values("23","1122","-1122");
insert into time_01 values("101412","4","-101219");
insert into time_01 values("24:59:09.932823","24:02:00.93282332424","24:20:34.00000000");
insert into time_01 values("2022-09-08 12:00:01","019","23403");

mysql> select * from time_01;
+-----------------------------------------------+
| t1 | t2 | t3 |
+-----------------------------------------------+
| -838:59:59 | 838:59:59 | 22:00:00 |
| 00:00:00 | 00:00:00 | 00:00:00 |
| NULL | NULL | NULL |
| 00:00:23 | 00:11:22 | -00:11:22 |
| 10:14:12 | 00:00:04 | -10:12:19 |
| 24:59:10 | 24:02:01 | 24:20:34 |
| 12:00:01 | 00:00:19 | 02:34:03 |
+-----------------------------------------------+
7 rows in set (0.00 sec)

mysql> select timediff(t1,t2) from time_01;
+------------------------+
| timediff(t1, t2) |
+------------------------+
| -1677:59:58 |
| 00:00:00 |
| NULL |
| -00:10:59 |
| 10:14:08 |
| 00:57:09 |
| 11:59:42 |
+------------------------+
7 rows in set (0.00 sec)
```