private boolean ruleActionToBoolean(final DataRetentionRuleAction action) {
        switch (action.getOutcome()) {
            case DELETE:
                return true;
            case RETAIN:
                return false;
            default:
                throw new RuntimeException("Unexpected type " + action.getOutcome().name());
        }
    }
@return True if any term in any rule expression uses at least one of {@code fields}.
stroom-meta/stroom-meta-impl-db/src/main/java/stroom/meta/impl/db/MetaDaoImpl.java