---

LEFT JOIN LATERAL (
    SELECT
        h.pension_rule_id
    FROM ourpension.npo_contract_pension_rules_history h
    WHERE h.contract_id = c.id
      AND h.period <= c.date
    ORDER BY
        h.period DESC,
        h.version DESC
    LIMIT 1
) prh ON true

LEFT JOIN ourpension.pension_rule pr
    ON pr.id = COALESCE(prh.pension_rule_id, c.pension_rule_id)