The Polars command line interface provides a convenient way to execute SQL commands using Polars as a backend.
The recommended way to install the Polars CLI is by using pip:
pip install polars-cliThis will install a pre-compiled binary and make it available on your path under polars.
If you do not have Python available, you can download a suitable binary from the most recent GitHub release.
Alternatively, you can install the Polars CLI using cargo, which will compile the code from scratch:
cargo install --locked polars-cliRunning polars without any arguments will start an interactive shell in which you can run SQL commands.
$ polars
Polars CLI version 0.4.0
Type .help for help.
>> select * FROM read_csv('examples/datasets/foods.csv');
┌────────────┬──────────┬────────┬──────────┐
│ category ┆ calories ┆ fats_g ┆ sugars_g │
│ --- ┆ --- ┆ --- ┆ --- │
│ str ┆ i64 ┆ f64 ┆ i64 │
╞════════════╪══════════╪════════╪══════════╡
│ vegetables ┆ 45 ┆ 0.5 ┆ 2 │
│ seafood ┆ 150 ┆ 5.0 ┆ 0 │
│ meat ┆ 100 ┆ 5.0 ┆ 0 │
│ fruit ┆ 60 ┆ 0.0 ┆ 11 │
│ … ┆ … ┆ … ┆ … │
│ seafood ┆ 200 ┆ 10.0 ┆ 0 │
│ seafood ┆ 200 ┆ 7.0 ┆ 2 │
│ fruit ┆ 60 ┆ 0.0 ┆ 11 │
│ meat ┆ 110 ┆ 7.0 ┆ 0 │
└────────────┴──────────┴────────┴──────────┘Alternatively, SQL commands can be piped directly into the Polars CLI.
$ echo "SELECT category FROM read_csv('examples/datasets/foods.csv')" | polars
┌────────────┐
│ category │
│ --- │
│ str │
╞════════════╡
│ vegetables │
│ seafood │
│ meat │
│ fruit │
│ … │
│ seafood │
│ seafood │
│ fruit │
│ meat │
└────────────┘When compiling the Polars CLI from source, the following features can be enabled:
| Feature | Description |
|---|---|
| default | The default feature set that includes all other features. |
| highlight | Provides syntax highlighting |
| parquet | Enables reading and writing of Apache Parquet files. |
| json | Enables reading and writing of JSON files. |
| ipc | Enables reading and writing of IPC/Apache Arrow files |