Rename columns across multiple tables in the same schema in Postgres

rename_multiple_columns.sql

-- Call function with the schema name
CREATE OR REPLACE FUNCTION rename_columns(_schema text) RETURNS VOID AS $func$
DECLARE
rec RECORD;
table RECORD;
result RECORD;
sql TEXT := '';
i INTEGER;

BEGIN

-- Use the information_schema to find out all of the table names in the input schema.
FOR rec IN
  SELECT table_name
  FROM information_schema.tables
  WHERE table_schema = _schema

-- Loop through all of the tables from the above statement renaming the columns:
LOOP
  EXECUTE format('ALTER TABLE %I.%I RENAME COLUMN original_column TO renamed_column', _schema, rec.table_name);
END LOOP;

END;
$func$ LANGUAGE PLPGSQL;