4.3 KiB
| toc_priority | toc_title |
|---|---|
| 53 | UUID |
Functions for Working with UUID
The functions for working with UUID are listed below.
generateUUIDv4
Generates the UUID of version 4.
generateUUIDv4()
Returned value
The UUID type value.
Usage example
This example demonstrates creating a table with the UUID type column and inserting a value into the table.
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)
Converts String type value to UUID type.
toUUID(String)
Returned value
The UUID type value.
Usage example
SELECT toUUID('61f0c404-5cb3-11e7-907b-a6006ad3dba0') AS uuid
┌─────────────────────────────────uuid─┐
│ 61f0c404-5cb3-11e7-907b-a6006ad3dba0 │
└──────────────────────────────────────┘
toUUIDOrNull (x)
It takes an argument of type String and tries to parse it into UUID. If failed, returns NULL.
toUUIDOrNull(String)
Returned value
The Nullable(UUID) type value.
Usage example
SELECT toUUIDOrNull('61f0c404-5cb3-11e7-907b-a6006ad3dba0T') AS uuid
┌─uuid─┐
│ ᴺᵁᴸᴸ │
└──────┘
toUUIDOrZero (x)
It takes an argument of type String and tries to parse it into UUID. If failed, returns zero UUID.
toUUIDOrZero(String)
Returned value
The UUID type value.
Usage example
SELECT toUUIDOrZero('61f0c404-5cb3-11e7-907b-a6006ad3dba0T') AS uuid
┌─────────────────────────────────uuid─┐
│ 00000000-0000-0000-0000-000000000000 │
└──────────────────────────────────────┘
UUIDStringToNum
Accepts a string containing 36 characters in the format xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx, and returns it as a set of bytes in a FixedString(16).
UUIDStringToNum(String)
Returned value
FixedString(16)
Usage examples
SELECT
'612f3c40-5d3b-217e-707b-6a546a3d7b29' AS uuid,
UUIDStringToNum(uuid) AS bytes
┌─uuid─────────────────────────────────┬─bytes────────────┐
│ 612f3c40-5d3b-217e-707b-6a546a3d7b29 │ a/<@];!~p{jTj={) │
└──────────────────────────────────────┴──────────────────┘
UUIDNumToString
Accepts a FixedString(16) value, and returns a string containing 36 characters in text format.
UUIDNumToString(FixedString(16))
Returned value
String.
Usage example
SELECT
'a/<@];!~p{jTj={)' AS bytes,
UUIDNumToString(toFixedString(bytes, 16)) AS uuid
┌─bytes────────────┬─uuid─────────────────────────────────┐
│ a/<@];!~p{jTj={) │ 612f3c40-5d3b-217e-707b-6a546a3d7b29 │
└──────────────────┴──────────────────────────────────────┘