ClickHouse/tests/integration/test_config_substitutions/configs/config_incl.xml

<yandex>
  <include_from>/etc/clickhouse-server/config.d/max_query_size.xml</include_from>
  <profiles>
    <default>
        <max_query_size incl="mqs" />
    </default>
  </profiles>
  <users>
      <default>
          <password></password>
          <profile>default</profile>
          <quota>default</quota>
      </default>
  </users>
</yandex>