mirror of
https://github.com/fluencelabs/sqlite-wasm-connector
synced 2025-03-31 13:31:07 +00:00
81 lines
2.2 KiB
Markdown
81 lines
2.2 KiB
Markdown
# SQLite [![Version][version-img]][version-url] [![Status][status-img]][status-url]
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The package provides an interface to [SQLite][1].
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## [Documentation][documentation]
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## Example
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Open a connection, create a table, and insert some rows:
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```rust
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let connection = sqlite::open(":memory:").unwrap();
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connection.execute("
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CREATE TABLE users (name TEXT, age INTEGER);
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INSERT INTO users (name, age) VALUES ('Alice', 42);
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INSERT INTO users (name, age) VALUES ('Bob', 69);
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").unwrap();
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```
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Select some rows and process them one by one as plain text:
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```rust
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connection.iterate("SELECT * FROM users WHERE age > 50", |pairs| {
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for &(column, value) in pairs.iter() {
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println!("{} = {}", column, value.unwrap());
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}
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true
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}).unwrap();
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```
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The same query using a prepared statement, which is much more efficient than the
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previous technique:
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```rust
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use sqlite::State;
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let mut statement = connection.prepare("
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SELECT * FROM users WHERE age > ?
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").unwrap();
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statement.bind(1, 50).unwrap();
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while let State::Row = statement.next().unwrap() {
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println!("name = {}", statement.read::<String>(0).unwrap());
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println!("age = {}", statement.read::<i64>(1).unwrap());
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}
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```
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The same query using a cursor, which is a wrapper around a prepared statement
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providing the concept of row and featuring all-at-once binding:
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```rust
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use sqlite::Value;
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let mut cursor = connection.prepare("
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SELECT * FROM users WHERE age > ?
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").unwrap().cursor();
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cursor.bind(&[Value::Integer(50)]).unwrap();
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while let Some(row) = cursor.next().unwrap() {
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println!("name = {}", row[0].as_string().unwrap());
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println!("age = {}", row[1].as_integer().unwrap());
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}
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```
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## Contribution
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Your contribution is highly appreciated. Do not hesitate to open an issue or a
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pull request. Note that any contribution submitted for inclusion in the project
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will be licensed according to the terms given in [LICENSE.md](LICENSE.md).
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[1]: https://www.sqlite.org
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[documentation]: https://docs.rs/sqlite
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[status-img]: https://travis-ci.org/stainless-steel/sqlite.svg?branch=master
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[status-url]: https://travis-ci.org/stainless-steel/sqlite
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[version-img]: https://img.shields.io/crates/v/sqlite.svg
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[version-url]: https://crates.io/crates/sqlite
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