{
    "_yql_read_udf"="Dsv.ReadRecord";
    "_yql_read_udf_run_config"="@@";
    "_yql_row_spec" = {
        "Type" = [
            "StructType";
            [
                [
                    "key";
                    [
                        "DataType";
                        "String"
                    ]
                ];
                [
                    "subkey";
                    [
                        "DataType";
                        "String"
                    ]
                ];
                [
                    "value";
                    [
                        "DataType";
                        "String"
                    ]
                ]
            ]
        ]
    }
}