sqlite's Introduction

SQLite

The package provides an interface to SQLite.

Example

Open a connection, create a table, and insert a few rows:

let connection = sqlite::open(":memory:").unwrap();

connection
    .execute(
        "
        CREATE TABLE users (name TEXT, age INTEGER);
        INSERT INTO users VALUES ('Alice', 42);
        INSERT INTO users VALUES ('Bob', 69);
        ",
    )
    .unwrap();

Select some rows and process them one by one as plain text:

connection
    .iterate("SELECT * FROM users WHERE age > 50", |pairs| {
        for &(column, value) in pairs.iter() {
            println!("{} = {}", column, value.unwrap());
        }
        true
    })
    .unwrap();

Run the same query but using a prepared statement, which is much more efficient than the previous technique:

use sqlite::State;

let mut statement = connection
    .prepare("SELECT * FROM users WHERE age > ?")
    .unwrap()
    .bind(1, 50)
    .unwrap();

while let Ok(State::Row) = statement.next() {
    println!("name = {}", statement.read::<String>(0).unwrap());
    println!("age = {}", statement.read::<i64>(1).unwrap());
}

Run the same query but using a cursor, which is a wrapper around a prepared statement providing the notion of row and featuring all-at-once binding:

use sqlite::Value;

let cursor = connection
    .prepare("SELECT * FROM users WHERE age > ?")
    .unwrap()
    .into_cursor()
    .bind(&[Value::Integer(50)])
    .unwrap();

for row in cursor.map(|row| row.unwrap()) {
    println!("name = {}", row.get::<String, _>("name"));
    println!("age = {}", row.get::<i64, _>("age"));
}

Contribution

Your contribution is highly appreciated. Do not hesitate to open an issue or a pull request. Note that any contribution submitted for inclusion in the project will be licensed according to the terms given in LICENSE.md.

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