psql> WITH today AS (
    ...SQL1...
), org_list AS (
    SELECT id AS org_id, ...SQL2...
), delivery_list AS (
    SELECT id AS org_id, ...SQL3...
), promo_list AS (
    SELECT id AS org_id, ...SQL4...
) INSERT INTO search_table SELECT ... FROM
    today, org_list AS o left join delivery_list AS d ON (d.org_id = o.org_id) left join promo_list AS p ON (p.org_id = o.org_id);

CREATE OR REPLACE FUNCTION table_search_rebuild() RETURNS void AS
$BODY$
TRUNCATE TABLE search_table;
WITH today AS (
    ...SQL1...
), org_list AS (
    SELECT id AS org_id, ...SQL2...
), delivery_list AS (
    SELECT id AS org_id, ...SQL3...
), promo_list AS (
    SELECT id AS org_id, ...SQL4...
) INSERT INTO search_table SELECT ... FROM
    today, org_list AS o left join delivery_list AS d ON (d.org_id = o.org_id) left join promo_list AS p ON (p.org_id = o.org_id)
$BODY$
  LANGUAGE sql VOLATILE
  COST 100;