read_nanoarrow {nanoarrow}

Read serialized streams of Arrow data

Description

Reads connections, file paths, URLs, or raw vectors of serialized Arrow data. Arrow documentation typically refers to this format as "Arrow IPC", since its origin was as a means to transmit tables between processes (e.g., multiple R sessions). This format can also be written to and read from files or URLs and is essentially a high performance equivalent of a CSV file that does a better job maintaining types.

Usage

read_nanoarrow(x, ..., lazy = FALSE)

example_ipc_stream()

Arguments

x

A raw() vector, connection, or file path from which to read binary data. Common extensions indicating compression (.gz, .bz2, .zip) are automatically uncompressed.

...

Currently unused.

lazy

By default, read_nanoarrow() will read and discard a copy of the reader's schema to ensure that invalid streams are discovered as soon as possible. Use lazy = TRUE to defer this check until the reader is actually consumed.

Details

The nanoarrow package does not currently have the ability to write serialized IPC data: use arrow::write_ipc_stream() to write data from R, or use the equivalent writer from another Arrow implementation in Python, C++, Rust, JavaScript, Julia, C#, and beyond.

The media type of an Arrow stream is application/vnd.apache.arrow.stream and the recommended file extension is .arrows.

Value

A nanoarrow_array_stream

Examples

as.data.frame(read_nanoarrow(example_ipc_stream()))