mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-10-09 18:10:48 +00:00
2e1f6bc56d
* replace exit with assert in test_single_page * improve save_raw_single_page docs option * More grammar fixes * "Built from" link in new tab * fix mistype * Example of include in docs * add anchor to meeting form * Draft of translation helper * WIP on translation helper * Replace some fa docs content with machine translation * add normalize-en-markdown.sh * normalize some en markdown * normalize some en markdown * admonition support * normalize * normalize * normalize * support wide tables * normalize * normalize * normalize * normalize * normalize * normalize * normalize * normalize * normalize * normalize * normalize * normalize * normalize * lightly edited machine translation of introdpection.md * lightly edited machhine translation of lazy.md * WIP on translation utils * Normalize ru docs * Normalize other languages * some fixes * WIP on normalize/translate tools * add requirements.txt * [experimental] add es docs language as machine translated draft * remove duplicate script * Back to wider tab-stop (narrow renders not so well)
108 lines
3.0 KiB
Markdown
108 lines
3.0 KiB
Markdown
# UUID函数 {#uuidhan-shu}
|
||
|
||
下面列出了所有UUID的相关函数
|
||
|
||
## generateUUIDv4 {#uuid-function-generate}
|
||
|
||
生成一个UUID（[版本4](https://tools.ietf.org/html/rfc4122#section-4.4)）。
|
||
|
||
``` sql
|
||
generateUUIDv4()
|
||
```
|
||
|
||
**返回值**
|
||
|
||
UUID类型的值。
|
||
|
||
**使用示例**
|
||
|
||
此示例演示如何在表中创建UUID类型的列，并对其写入数据。
|
||
|
||
``` sql
|
||
:) CREATE TABLE t_uuid (x UUID) ENGINE=TinyLog
|
||
|
||
:) INSERT INTO t_uuid SELECT generateUUIDv4()
|
||
|
||
:) SELECT * FROM t_uuid
|
||
|
||
┌────────────────────────────────────x─┐
|
||
│ f4bf890f-f9dc-4332-ad5c-0c18e73f28e9 │
|
||
└──────────────────────────────────────┘
|
||
```
|
||
|
||
## toUUID (x) {#touuid-x}
|
||
|
||
将String类型的值转换为UUID类型的值。
|
||
|
||
``` sql
|
||
toUUID(String)
|
||
```
|
||
|
||
**返回值**
|
||
|
||
UUID类型的值
|
||
|
||
**使用示例**
|
||
|
||
``` sql
|
||
:) SELECT toUUID('61f0c404-5cb3-11e7-907b-a6006ad3dba0') AS uuid
|
||
|
||
┌─────────────────────────────────uuid─┐
|
||
│ 61f0c404-5cb3-11e7-907b-a6006ad3dba0 │
|
||
└──────────────────────────────────────┘
|
||
```
|
||
|
||
## UUIDStringToNum {#uuidstringtonum}
|
||
|
||
接受一个String类型的值，其中包含36个字符且格式为`xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx`，将其转换为UUID的数值并以[FixedString(16)](../../data_types/fixedstring.md)将其返回。
|
||
|
||
``` sql
|
||
UUIDStringToNum(String)
|
||
```
|
||
|
||
**返回值**
|
||
|
||
FixedString(16)
|
||
|
||
**使用示例**
|
||
|
||
``` sql
|
||
:) SELECT
|
||
'612f3c40-5d3b-217e-707b-6a546a3d7b29' AS uuid,
|
||
UUIDStringToNum(uuid) AS bytes
|
||
|
||
┌─uuid─────────────────────────────────┬─bytes────────────┐
|
||
│ 612f3c40-5d3b-217e-707b-6a546a3d7b29 │ a/<@];!~p{jTj={) │
|
||
└──────────────────────────────────────┴──────────────────┘
|
||
```
|
||
|
||
## UUIDNumToString {#uuidnumtostring}
|
||
|
||
接受一个[FixedString(16)](../../data_types/fixedstring.md)类型的值，返回其对应的String表现形式。
|
||
|
||
``` sql
|
||
UUIDNumToString(FixedString(16))
|
||
```
|
||
|
||
**返回值**
|
||
|
||
String.
|
||
|
||
**使用示例**
|
||
|
||
``` sql
|
||
SELECT
|
||
'a/<@];!~p{jTj={)' AS bytes,
|
||
UUIDNumToString(toFixedString(bytes, 16)) AS uuid
|
||
|
||
┌─bytes────────────┬─uuid─────────────────────────────────┐
|
||
│ a/<@];!~p{jTj={) │ 612f3c40-5d3b-217e-707b-6a546a3d7b29 │
|
||
└──────────────────┴──────────────────────────────────────┘
|
||
```
|
||
|
||
## 另请参阅 {#ling-qing-can-yue}
|
||
|
||
- [dictGetUUID](ext_dict_functions.md)
|
||
|
||
[来源文章](https://clickhouse.tech/docs/en/query_language/functions/uuid_function/) <!--hide-->
|