duckdb / duckdb-rs

Ergonomic bindings to duckdb for Rust
MIT License
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duckdb-rs

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duckdb-rs is an ergonomic wrapper for using duckdb from Rust. It attempts to expose an interface similar to rusqlite. Actually the initial code and even this README is forked from rusqlite as duckdb also tries to expose a sqlite3 compatible API.

use duckdb::{params, Connection, Result};

// In your project, we need to keep the arrow version same as the version used in duckdb.
// Refer to https://github.com/wangfenjin/duckdb-rs/issues/92
// You can either:
use duckdb::arrow::record_batch::RecordBatch;
// Or in your Cargo.toml, use * as the version; features can be toggled according to your needs
// arrow = { version = "*", default-features = false, features = ["prettyprint"] }
// Then you can:
// use arrow::record_batch::RecordBatch;

use duckdb::arrow::util::pretty::print_batches;

#[derive(Debug)]
struct Person {
    id: i32,
    name: String,
    data: Option<Vec<u8>>,
}

fn main() -> Result<()> {
    let conn = Connection::open_in_memory()?;

    conn.execute_batch(
        r"CREATE SEQUENCE seq;
          CREATE TABLE person (
                  id              INTEGER PRIMARY KEY DEFAULT NEXTVAL('seq'),
                  name            TEXT NOT NULL,
                  data            BLOB
                  );
        ")?;

    let me = Person {
        id: 0,
        name: "Steven".to_string(),
        data: None,
    };
    conn.execute(
        "INSERT INTO person (name, data) VALUES (?, ?)",
        params![me.name, me.data],
    )?;

    // query table by rows
    let mut stmt = conn.prepare("SELECT id, name, data FROM person")?;
    let person_iter = stmt.query_map([], |row| {
        Ok(Person {
            id: row.get(0)?,
            name: row.get(1)?,
            data: row.get(2)?,
        })
    })?;

    for person in person_iter {
        let p = person.unwrap();
        println!("ID: {}", p.id);
        println!("Found person {:?}", p);
    }

    // query table by arrow
    let rbs: Vec<RecordBatch> = stmt.query_arrow([])?.collect();
    print_batches(&rbs).unwrap();
    Ok(())
}

Notes on building duckdb and libduckdb-sys

libduckdb-sys is a separate crate from duckdb-rs that provides the Rust declarations for DuckDB's C API. By default, libduckdb-sys attempts to find a DuckDB library that already exists on your system using pkg-config, or a Vcpkg installation for MSVC ABI builds.

You can adjust this behavior in a number of ways:

Binding generation

We use bindgen to generate the Rust declarations from DuckDB's C header file. bindgen recommends running this as part of the build process of libraries that used this. We tried this briefly (duckdb 0.10.0, specifically), but it had some annoyances:

So we try to avoid running bindgen at build-time by shipping pregenerated bindings for DuckDB.

If you use the bundled features, you will get pregenerated bindings for the bundled version of DuckDB. If you want to run bindgen at buildtime to produce your own bindings, use the buildtime_bindgen Cargo feature.

Contributing

See to Contributing.md

Checklist

TODOs

License

DuckDB and libduckdb-sys are available under the MIT license. See the LICENSE file for more info.