ClickHouse/tests/performance/empty_string_deserialization.xml

<test>
    <!-- gcc-8 generates 20% faster code than gcc-9
         clang-8 generates more than two times slower code than gcc
      -->

    <create_query>CREATE TABLE empty_strings (s String) ENGINE = Log;</create_query>
    <fill_query>INSERT INTO empty_strings SELECT '' FROM zeros_mt(1000000000);</fill_query>

    <query>SELECT count() FROM empty_strings WHERE NOT ignore(s)</query>

    <drop_query>DROP TABLE IF EXISTS empty_strings</drop_query>
</test>