array_fill() — PostgreSQL array function

array_fill(): array constructor with value. PostgreSQL array functions — signature, volatility, version applicability and an illustrative example.

Summary

array_fill is a PostgreSQL built-in function in the Array Functions group. PostgreSQL’s system catalog (pg_proc) describes it as: “array constructor with value”.

Signature

array_fill has 2 documented overloaded forms:

array_fill(anyelement, integer[]) → anyarray
array_fill(anyelement, integer[], integer[]) → anyarray

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: Array 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: anyarray

Example

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

SELECT array_fill(1, ARRAY[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

array_fill 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 — Array Functions.