PostgreSQL PL/pgSQL procedure: creates staging table of numbered, text columns (f1, f2, f3…)

procedure-create_text_table.sql

CREATE PROCEDURE create_text_table (fields INT, tablename TEXT = '_import')
AS $$
/*
DESCRIPTION       create text-only staging table
  ARGUMENTS       fields: number of fields (columns)
                  tablename: [optional, default='_import'] name of table
*/
DECLARE
  fieldlist TEXT := '';
BEGIN
  SELECT string_agg(field, ', ' ORDER BY n)
    FROM (SELECT 'f' || n || ' text' AS field, n
            FROM generate_series(1, fields) AS gs(n) ) sq
    INTO fieldlist;

  EXECUTE FORMAT('CREATE UNLOGGED TABLE %I (%s)', tablename, fieldlist);

  RAISE NOTICE '✅ created table % (% text fields)', tablename, fields;
END; $$
LANGUAGE plpgsql;

COMMENT ON PROCEDURE create_text_table(INT, TEXT) IS
  'create unlogged table with specified # of text fields';