PG::UndefinedFunction: ERROR: function array_append(anyarray, anyelement) does not exist

Question

In my application we have few test cases which are configured with GitHub workflow,Even I do have only space related changes on file but still getting below error. Not sure why my specs are still failing it was working fine before.

An error occurred in a `before(:suite)` hook.
Failure/Error: ActiveMedian.create_function

ActiveRecord::StatementInvalid:
  PG::UndefinedFunction: ERROR:  function array_append(anyarray, anyelement) does not exist
  :       CREATE OR REPLACE FUNCTION median(anyarray)
           RETURNS float8 AS
        $$
          WITH q AS
          (
             SELECT val
             FROM unnest($***) val
             WHERE VAL IS NOT NULL
             ORDER BY ***
          ),
          cnt AS
          (
            SELECT COUNT(*) AS c FROM q
          )
          SELECT AVG(val)::float8
          FROM
          (
            SELECT val FROM q
            LIMIT  2 - MOD((SELECT c FROM cnt), 2)
            OFFSET GREATEST(CEIL((SELECT c FROM cnt) / 2.0) - ***,0)
          ) q2;
        $$
        LANGUAGE sql IMMUTABLE;

        DROP AGGREGATE IF EXISTS median(numeric);
        DROP AGGREGATE IF EXISTS median(double precision);
        DROP AGGREGATE IF EXISTS median(anyelement);
        CREATE AGGREGATE median(anyelement) (
          SFUNC=array_append,
          STYPE=anyarray,
          FINALFUNC=median,
          INITCOND='{}'
        );
# ./spec/rails_helper.rb:***54:in `seed'
# ./spec/rails_helper.rb:***:in `block (2 levels) in <top (required)>'
# ------------------
# --- Caused by: ---

# PG::UndefinedFunction:
#   ERROR:  function array_append(anyarray, anyelement) does not exist
#   ./spec/rails_helper.rb:***54:in `seed'

There is ActiveMedian.create_function on spec/rails_helper.rb which might causing the issue.

Any lead or suggestion would be appreciated

Answer 1

After a few research, I have resolved this issue by changing the Postgres image version on GitHub as follows.

file .github/workflows/build.yml

services:
      postgres:
        image: postgres:13
        ports:
          - 5432:5432

Solution: This is an issue with Postgres 14 version, For quick solve downgrade it to Postgres 13.