Crate duckdb 

duckdb-rs is an ergonomic wrapper for using DuckDB from Rust. It attempts to expose an interface similar to rusqlite.

use duckdb::{params, Connection, Result};
use duckdb::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],
    )?;

    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 {
        println!("Found person {:?}", person.unwrap());
    }

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

Re-exports

pub use crate::types::ToSql;

pub use libduckdb_sys as ffi;

pub use arrow;

pub use polars;

pub use polars_arrow as arrow2;

Modules

core

The core module contains the main functionality of the DuckDB crate.

types

ToSql and FromSql are also implemented for Option<T> where T implements ToSql or FromSql for the cases where you want to know if a value was NULL (which gets translated to None).

vscalar

The duckdb scalar function interface

vtab

The duckdb table function interface

Macros

params

A macro making it more convenient to pass heterogeneous or long lists of parameters as a &[&dyn ToSql].

Structs

AndThenRows

An iterator over the mapped resulting rows of a query, with an Error type unifying with Error.

Appender

Appender for fast import data

AppenderParamsFromIter

Adapter type which allows any iterator over ToSql values to implement [Params].

Arrow

A handle for the resulting RecordBatch of a query.

ArrowStream

A handle for the resulting RecordBatch of a query in streaming

CachedStatement

Cacheable statement.

Column

Information about a column of a DuckDB query.

Config

duckdb configuration Refer to https://github.com/duckdb/duckdb/blob/master/src/main/config.cpp

Connection

A connection to a DuckDB database.

DuckdbConnectionManager

An r2d2::ManageConnection for duckdb::Connections.

InterruptHandle

A handle that allows interrupting long-running queries.

Map

F is used to transform the streaming iterator into a fallible iterator.

MappedRows

An iterator over the mapped resulting rows of a query.

ParamsFromIter

Adapter type which allows any iterator over ToSql values to implement Params.

Polars

An handle for the resulting Polars DataFrame of a query.

Row

A single result row of a query.

Rows

An handle for the resulting rows of a query.

Statement

A prepared statement.

Transaction

Represents a transaction on a database connection.

Enums

AccessMode

duckdb access mode, default is Automatic

DatabaseName

Name for a database within a DuckDB connection.

DefaultNullOrder

duckdb default null order, default is nulls first

DefaultOrder

duckdb default order, default is Asc

DropBehavior

Options for how a Transaction should behave when it is dropped.

Error

Enum listing possible errors from duckdb.

ErrorCode

Error Codes

Constants

MAIN_DB

Shorthand for DatabaseName::Main.

TEMP_DB

Shorthand for DatabaseName::Temp.

Traits

AppenderParams

Trait used for sets of parameter passed into SQL statements/queries.

OptionalExt

See the method documentation.

Params

Trait used for sets of parameter passed into SQL statements/queries.

RowIndex

A trait implemented by types that can index into columns of a row.

Functions

appender_params_from_iter

Constructor function for a [ParamsFromIter]. See its documentation for more.

params_from_iter

Constructor function for a ParamsFromIter. See its documentation for more.

Type Aliases

Result

A typedef of the result returned by many methods.