columns {
  name: "l_orderkey"
  type {
    type_id: INT32
  }
}
columns {
  name: "revenue"
  type {
    type_id: DOUBLE
  }
}
columns {
  name: "o_orderdate"
  type {
    optional_type {
      item {
        type_id: DATE
      }
    }
  }
}
columns {
  name: "o_shippriority"
  type {
    type_id: INT64
  }
}
