polars_arrow::io::ipc

Module read

Source
Available on crate feature io_ipc only.
Expand description

APIs to read Arrow’s IPC format.

The two important structs here are the FileReader, which provides arbitrary access to any of its messages, and the StreamReader, which only supports reading data in the order it was written in.

Structs§

FileMetadata
Metadata of an Arrow IPC file, written in the footer of the file.
FileReader
An iterator of RecordBatchTs from an Arrow IPC file.
FlightConsumer
FlightStreamProducer
FlightstreamConsumer
ProjectionInfo
StreamMetadata
Metadata of an Arrow IPC stream, written at the start of the stream
StreamReader
Arrow Stream reader.

Enums§

OutOfSpecKind
The different types of errors that reading from IPC can cause
StreamState
Encodes the stream’s status after each read.

Traits§

SendableIterator

Functions§

deserialize_footer
deserialize_schema
Deserialize an flatbuffers-encoded Schema message into ArrowSchema and IpcSchema.
get_row_count
Read the row count by summing the length of the of the record batches
get_row_count_from_blocks
Read the row count by summing the length of the of the record batches in blocks
into_flight_stream
prepare_projection
read_batch
Reads the record batch at position index from the reader.
read_file_dictionaries
Reads all file’s dictionaries, if any This function is IO-bounded
read_file_metadata
Read the Arrow IPC file’s metadata
read_stream_metadata
Reads the metadata of the stream

Type Aliases§

Dictionaries
how dictionaries are tracked in this crate