gcd() — PostgreSQL mathematical function

gcd(): greatest common divisor. PostgreSQL mathematical functions — signature, volatility, version applicability and an illustrative example.

Summary

gcd is a PostgreSQL built-in function in the Mathematical Functions group. PostgreSQL’s system catalog (pg_proc) describes it as: “greatest common divisor”.

Signature

gcd has 3 documented overloaded forms:

gcd(integer, integer) → integer
gcd(bigint, bigint) → bigint
gcd(numeric, numeric) → numeric

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: Mathematical 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, integer, numeric

Example

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

SELECT gcd(42, 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

gcd 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 — Mathematical Functions.