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9.14. UUID Functions
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9.14. UUID Functions#

Table 9.45 shows thePostgreSQL functions that can be used to generate UUIDs.

Table 9.45. UUID Generation Functions

Function Description Example(s)
`gen_random_uuid` →`uuid` `uuidv4` →`uuid` Generate a version 4 (random) UUID. `gen_random_uuid()` →`5b30857f-0bfa-48b5-ac0b-5c64e28078d1` `uuidv4()` →`b42410ee-132f-42ee-9e4f-09a6485c95b8`
`uuidv7` ( [`shift``interval`] ) →`uuid` Generate a version 7 (time-ordered) UUID. The timestamp is computed using UNIX timestamp with millisecond precision + sub-millisecond timestamp + random. The optional parameter`shift` will shift the computed timestamp by the given`interval`. `uuidv7()` →`019535d9-3df7-79fb-b466-fa907fa17f9e`

Function

Description

Example(s)

gen_random_uuid →uuid

uuidv4 →uuid

Generate a version 4 (random) UUID.

gen_random_uuid() →5b30857f-0bfa-48b5-ac0b-5c64e28078d1

uuidv4() →b42410ee-132f-42ee-9e4f-09a6485c95b8

uuidv7 ( [shiftinterval] ) →uuid

Generate a version 7 (time-ordered) UUID. The timestamp is computed using UNIX timestamp with millisecond precision + sub-millisecond timestamp + random. The optional parametershift will shift the computed timestamp by the giveninterval.

uuidv7() →019535d9-3df7-79fb-b466-fa907fa17f9e

Note

The uuid-ossp module provides additional functions that implement other standard algorithms for generating UUIDs.

Table 9.46 shows thePostgreSQL functions that can be used to extract information from UUIDs.

Table 9.46. UUID Extraction Functions

Function Description Example(s)
`uuid_extract_timestamp` (`uuid` ) →`timestamp with time zone` Extracts a`timestamp with time zone` from UUID version 1 and 7. For other versions, this function returns null. Note that the extracted timestamp is not necessarily exactly equal to the time the UUID was generated; this depends on the implementation that generated the UUID. `uuid_extract_timestamp('019535d9-3df7-79fb-b466-fa907fa17f9e'::uuid)` →`2025-02-23 21:46:24.503-05`
`uuid_extract_version` (`uuid` ) →`smallint` Extracts the version from a UUID of the variant described byRFC 9562. For other variants, this function returns null. For example, for a UUID generated by`gen_random_uuid`, this function will return 4. `uuid_extract_version('41db1265-8bc1-4ab3-992f-885799a4af1d'::uuid)` →`4` `uuid_extract_version('019535d9-3df7-79fb-b466-fa907fa17f9e'::uuid)` →`7`

Function

Description

Example(s)

uuid_extract_timestamp (uuid ) →timestamp with time zone

Extracts atimestamp with time zone from UUID version 1 and 7. For other versions, this function returns null. Note that the extracted timestamp is not necessarily exactly equal to the time the UUID was generated; this depends on the implementation that generated the UUID.

uuid_extract_timestamp('019535d9-3df7-79fb-b466-fa907fa17f9e'::uuid) →2025-02-23 21:46:24.503-05

uuid_extract_version (uuid ) →smallint

Extracts the version from a UUID of the variant described byRFC 9562. For other variants, this function returns null. For example, for a UUID generated bygen_random_uuid, this function will return 4.

uuid_extract_version('41db1265-8bc1-4ab3-992f-885799a4af1d'::uuid) →4

uuid_extract_version('019535d9-3df7-79fb-b466-fa907fa17f9e'::uuid) →7

PostgreSQL also provides the usual comparison operators shown in Table 9.1 for UUIDs.

SeeSection 8.12 for details on the data typeuuid inPostgreSQL.

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