datastore/tests/performance/prewhere_subcolumns.xml

<test>
    <settings>
        <max_threads>1</max_threads>
        <use_variant_as_common_type>1</use_variant_as_common_type>
    </settings>

    <create_query>create table test (x UInt32, n Nullable(UInt32), s String, t Tuple(a UInt32, b String), json JSON) engine=MergeTree order by tuple()</create_query>
    <fill_query>insert into test select number, number = 0 ? NULL : number, repeat('a', 1000), tuple(number, randomString(1000)), toJSONString(map('a', number::Int32, 'b', repeat('a', 1000))) from numbers(1000000)</fill_query>

    <query>select * from test where t.a = 42 format Null</query>
    <query>select * from test where n.null format Null</query>
    <query>select * from test where json.a = 42 format Null</query>

    <drop_query>drop table if exists test</drop_query>
</test>