{
    "schema"=<"strict"=%true; "unique_keys"=%false>[
        {"name"="key";"type"="string";"required"=%true};
        {"name"="subkey";"type"="string";"required"=%true};
        {"name"="value";"type"="string";"required"=%true};
    ];
    "_yql_row_spec"={
        "Type"=["StructType";[
            ["key";["DataType";"String"]];
        ]];
    };
}