def to_arrow_table(self):
"""Return arrow table object created from the DataTable."""
from pyarrow import Table, array
arrow_table = Table.from_arrays(
[array(column) for column in list(map(list, zip(*self._data)))],
names=self.columns)
return arrow_table
def send_data(self, command: bytes, table: Optional[Table]) -> None:
"""
Send a data batch to the server.
:param command: a command to in descriptor to pass along, user should take the responsibility to
deserialize it.
:param table: a PyArrow.Table of column-stored records.
"""
descriptor = FlightDescriptor.for_command(command)
table = Table.from_arrays([]) if table is None else table
writer, _ = self.do_put(descriptor, table.schema)
writer: FlightStreamWriter
with writer:
writer.write_table(table)
def select(self, columns):
""" ArrowLoaf: Selected columns in selected order. """
return type(self)(Table.from_arrays([self[x] for x in columns]))
