ClickHouse/tests/integration/test_dictionaries_update_and_reload/configs/dictionaries/executable.xml

<?xml version="1.0"?>
<yandex>
  <dictionary>
    <name>executable</name>
    <source>
      <executable>
        <command>echo '7\t8';</command>
        <format>TabSeparated</format>
      </executable>
    </source>
    <lifetime>0</lifetime>
    <layout><flat/></layout>
    <structure><id><name>key</name> </id>
      <attribute><name>a</name><type>Int32</type>
        <null_value>0</null_value>
      </attribute>
    </structure>
  </dictionary>
</yandex>