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# convert_tz

## Syntax

`DATETIME CONVERT_TZ(DATETIME dt, VARCHAR from_tz, VARCHAR to_tz)`

## Description

转换datetime值dt，从 from_tz 由给定转到 to_tz 时区给出的时区，并返回的结果值。 如果参数无效该函数返回NULL。

## Examples

```
mysql> select convert_tz('2019-08-01 13:21:03', 'Asia/Shanghai', 'America/Los_Angeles');
+---------------------------------------------------------------------------+
| convert_tz('2019-08-01 13:21:03', 'Asia/Shanghai', 'America/Los_Angeles') |
+---------------------------------------------------------------------------+
| 2019-07-31 22:21:03                                                       |
+---------------------------------------------------------------------------+

mysql> select convert_tz('2019-08-01 13:21:03', '+08:00', 'America/Los_Angeles');
+--------------------------------------------------------------------+
| convert_tz('2019-08-01 13:21:03', '+08:00', 'America/Los_Angeles') |
+--------------------------------------------------------------------+
| 2019-07-31 22:21:03                                                |
+--------------------------------------------------------------------+
```

## keyword

    CONVERT_TZ