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| |
| # Apache Parquet Official Native Rust Implementation |
| |
| [](https://crates.io/crates/parquet) |
| [](https://docs.rs/parquet/latest/parquet/) |
| |
| This crate contains the official Native Rust implementation of [Apache Parquet](https://parquet.apache.org/), which is part of the [Apache Arrow](https://arrow.apache.org/) project. |
| |
| See the [API documentation](https://docs.rs/parquet/latest) for examples and the full API. |
| |
| The API documentation for most recent, unreleased code is available [here](https://arrow.apache.org/rust/parquet/index.html). |
| |
| ## Rust Version Compatibility |
| |
| This crate is tested with the latest stable version of Rust. We do not currently test against other, older versions of the Rust compiler. |
| |
| ## Versioning / Releases |
| |
| The arrow crate follows the [SemVer standard](https://doc.rust-lang.org/cargo/reference/semver.html) defined by Cargo and works well within the Rust crate ecosystem. |
| |
| However, for historical reasons, this crate uses versions with major numbers greater than `0.x` (e.g. `19.0.0`), unlike many other crates in the Rust ecosystem which spend extended time releasing versions `0.x` to signal planned ongoing API changes. Minor arrow releases contain only compatible changes, while major releases may contain breaking API changes. |
| |
| ## Feature Flags |
| |
| The `parquet` crate provides the following features which may be enabled in your `Cargo.toml`: |
| |
| - `arrow` (default) - support for reading / writing [`arrow`](https://crates.io/crates/arrow) arrays to / from parquet |
| - `async` - support `async` APIs for reading parquet |
| - `json` - support for reading / writing `json` data to / from parquet |
| - `brotli` (default) - support for parquet using `brotli` compression |
| - `flate2` (default) - support for parquet using `gzip` compression |
| - `lz4` (default) - support for parquet using `lz4` compression |
| - `zstd` (default) - support for parquet using `zstd` compression |
| - `snap` (default) - support for parquet using `snappy` compression |
| - `cli` - parquet [CLI tools](https://github.com/apache/arrow-rs/tree/master/parquet/src/bin) |
| - `experimental` - Experimental APIs which may change, even between minor releases |
| |
| ## Parquet Feature Status |
| |
| - [x] All encodings supported |
| - [x] All compression codecs supported |
| - [x] Read support |
| - [x] Primitive column value readers |
| - [x] Row record reader |
| - [x] Arrow record reader |
| - [x] Async support (to Arrow) |
| - [x] Statistics support |
| - [x] Write support |
| - [x] Primitive column value writers |
| - [ ] Row record writer |
| - [x] Arrow record writer |
| - [x] Async support |
| - [x] Predicate pushdown |
| - [x] Parquet format 4.0.0 support |
| |
| ## Support for `wasm32-unknown-unknown` target |
| |
| It's possible to build `parquet` for the `wasm32-unknown-unknown` target, however not all the compression features are currently unsupported due to issues with the upstream crates. In particular, the `zstd` and `lz4` features may have compilation issues. See issue [#180](https://github.com/apache/arrow-rs/issues/180). |
| |
| ``` |
| cargo build -p parquet --target wasm32-unknown-unknown --no-default-features --features cli,snap,flate2,brotli |
| ``` |
| |
| ## License |
| |
| Licensed under the Apache License, Version 2.0: http://www.apache.org/licenses/LICENSE-2.0. |
