ydb/yt/yql/tests/sql/suites/lineage/input2.txt.attr

{
    "_yql_row_spec"={
       "Type"=["StructType";[
           ["k2";["OptionalType";["DataType";"Int32";];];];
           ["a2";["DataType";"Int32";];];
           ["b2";["DataType";"Int32";];];
           ["c2";["OptionalType";["DataType";"Int32";];];];
           ["d2";["DataType";"Int32";];];
       ];];
    }
}