generate_subscripts() — PostgreSQL array function

generate_subscripts(): array subscripts generator. PostgreSQL array functions — signature, volatility, version applicability and an illustrative example.

The Sev-1 Admin
The Sev-1 Admin  ·  2 min read

Summary

generate_subscripts is a PostgreSQL built-in function in the Array Functions group. PostgreSQL’s system catalog (pg_proc) describes it as: “array subscripts generator”.

Signature

generate_subscripts has 2 documented overloaded forms:

generate_subscripts(anyarray, integer, boolean) → setof integer
generate_subscripts(anyarray, integer) → setof integer

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: integer (set-returning)

Example

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

SELECT * FROM generate_subscripts(ARRAY[1,2,3], 42, true);

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

generate_subscripts 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.