length() — PostgreSQL geometric function

length(): length. PostgreSQL geometric functions — signature, volatility, version applicability and an illustrative example.

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

Summary

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

Signature

length has 8 documented overloaded forms:

length(text) → integer
length(character) → integer
length(lseg) → double precision
length(path) → double precision
length(bytea, name) → integer
length(bit) → integer
length(bytea) → integer
length(tsvector) → 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: Geometric 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: double precision, integer

Example

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

SELECT length('abc');

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

length 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 — Geometric Functions.