bdeb626c5a
### What changes were proposed in this pull request? This PR adds the SQL standard command - `SET TIME ZONE` to the current default time zone displacement for the current SQL-session, which is the same as the existing `set spark.sql.session.timeZone=xxx'. All in all, this PR adds syntax as following, ``` SET TIME ZONE LOCAL; SET TIME ZONE 'valid time zone'; -- zone offset or region SET TIME ZONE INTERVAL XXXX; -- xxx must in [-18, + 18] hours, * this range is bigger than ansi [-14, + 14] ``` ### Why are the changes needed? ANSI compliance and supply pure SQL users a way to retrieve all supported TimeZones ### Does this PR introduce _any_ user-facing change? yes, add new syntax. ### How was this patch tested? add unit tests. and locally verified reference doc ![image](https://user-images.githubusercontent.com/8326978/87510244-c8dc3680-c6a5-11ea-954c-b098be84afee.png) Closes #29064 from yaooqinn/SPARK-32272. Authored-by: Kent Yao <yaooqinn@hotmail.com> Signed-off-by: Wenchen Fan <wenchen@databricks.com>
68 lines
2.4 KiB
Markdown
68 lines
2.4 KiB
Markdown
---
|
|
layout: global
|
|
title: SET TIME ZONE
|
|
displayTitle: SET TIME ZONE
|
|
license: |
|
|
Licensed to the Apache Software Foundation (ASF) under one or more
|
|
contributor license agreements. See the NOTICE file distributed with
|
|
this work for additional information regarding copyright ownership.
|
|
The ASF licenses this file to You under the Apache License, Version 2.0
|
|
(the "License"); you may not use this file except in compliance with
|
|
the License. You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
---
|
|
|
|
### Description
|
|
|
|
The SET TIME ZONE command sets the time zone of the current session.
|
|
|
|
### Syntax
|
|
|
|
```sql
|
|
SET TIME ZONE LOCAL
|
|
SET TIME ZONE 'timezone_value'
|
|
SET TIME ZONE INTERVAL interval_literal
|
|
```
|
|
|
|
### Parameters
|
|
|
|
* **LOCAL**
|
|
|
|
Set the time zone to the one specified in the java `user.timezone` property, or to the environment variable `TZ` if `user.timezone` is undefined, or to the system time zone if both of them are undefined.
|
|
|
|
* **timezone_value**
|
|
|
|
The ID of session local timezone in the format of either region-based zone IDs or zone offsets. Region IDs must have the form 'area/city', such as 'America/Los_Angeles'. Zone offsets must be in the format '`(+|-)HH`', '`(+|-)HH:mm`' or '`(+|-)HH:mm:ss`', e.g '-08', '+01:00' or '-13:33:33'. Also, 'UTC' and 'Z' are supported as aliases of '+00:00'. Other short names are not recommended to use because they can be ambiguous.
|
|
|
|
* **interval_literal**
|
|
|
|
The [interval literal](sql-ref-literals.html#interval-literal) represents the difference between the session time zone to the 'UTC'. It must be in the range of [-18, 18] hours and max to second precision, e.g. `INTERVAL 2 HOURS 30 MINITUES` or `INTERVAL '15:40:32' HOUR TO SECOND`.
|
|
|
|
### Examples
|
|
|
|
```sql
|
|
-- Set time zone to the system default.
|
|
SET TIME ZONE LOCAL;
|
|
|
|
-- Set time zone to the region-based zone ID.
|
|
SET TIME ZONE 'America/Los_Angeles';
|
|
|
|
-- Set time zone to the Zone offset.
|
|
SET TIME ZONE '+08:00';
|
|
|
|
-- Set time zone with intervals.
|
|
SET TIME ZONE INTERVAL 1 HOUR 30 MINUTES;
|
|
SET TIME ZONE INTERVAL '08:30:00' HOUR TO SECOND;
|
|
```
|
|
|
|
### Related Statements
|
|
|
|
* [SET](sql-ref-syntax-aux-conf-mgmt-set.html)
|