uuid_hash_extended() — PostgreSQL UUID function

uuid_hash_extended(): hash. PostgreSQL uuid functions — signature, volatility, version applicability and an illustrative example.

The Sev-1 Admin
The Sev-1 Admin  ·  1 min read

Summary

uuid_hash_extended is a PostgreSQL built-in function in the UUID Functions group. PostgreSQL’s system catalog (pg_proc) describes it as: “hash”.

Signature

uuid_hash_extended(uuid, bigint) → bigint

Argument and return types are taken from the pg_proc catalog; internal type names are shown using their readable SQL spellings (for example int4 is shown as integer). (Derived from the catalog — see the linked reference for the canonical documentation.)

Classification

  • Category: UUID Functions
  • Kind: Function
  • Volatility: IMMUTABLE — Marked IMMUTABLE — it always returns the same result for the same arguments and can be used in indexes and other contexts that require immutability.
  • Returns: bigint

Example

Illustrative form (replace placeholder values with your own data):

SELECT uuid_hash_extended(gen_random_uuid(), 42);

The example above is illustrative and is meant to show calling syntax only; consult the linked PostgreSQL documentation for exact semantics, edge cases and accepted argument combinations.

Version applicability

uuid_hash_extended is present across the surveyed releases (PostgreSQL 15, 16, 17, 18, 19). On older major versions, behaviour may differ in detail — always check the documentation for the version you run.

Related & references

Reference: PostgreSQL documentation — UUID Functions.