Module polars_arrow::io::ipc::read

Available on crate feature io_ipc only.

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.

Modules

• file_asyncio_ipc_read_async
  Async reader for Arrow IPC files
• stream_asyncio_ipc_read_async
  APIs to read Arrow streams asynchronously

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.
• 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.

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
• 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