{"_yql_row_spec"={
    "Type"=["StructType";[
        ["key";["DataType";"String"]];
        ["subkey";["DataType";"String"]];
        ["value";["DataType";"Utf8"]]
    ]];
    "SortDirections"=[1;1;1;];
    "SortedBy"=["key";"subkey";"value";];
    "SortedByTypes"=[["DataType";"String";];["DataType";"String";];["DataType";"Utf8";];];
    "SortMembers"=["key";"subkey";"value";];
}}