mirror of
https://github.com/fluencelabs/sqlite-wasm-connector
synced 2025-03-15 06:20:50 +00:00
87 lines
2.3 KiB
Markdown
87 lines
2.3 KiB
Markdown
# SQLite [![Package][package-img]][package-url] [![Documentation][documentation-img]][documentation-url] [![Build][build-img]][build-url]
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The package provides an interface to [SQLite][1].
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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
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.execute(
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"
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CREATE TABLE users (name TEXT, age INTEGER);
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INSERT INTO users VALUES ('Alice', 42);
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INSERT INTO users VALUES ('Bob', 69);
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",
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)
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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
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.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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})
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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
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the previous technique:
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```rust
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use sqlite::State;
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let mut statement = connection
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.prepare("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
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statement 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
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.prepare("SELECT * FROM users WHERE age > ?")
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.unwrap()
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.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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[build-img]: https://travis-ci.org/stainless-steel/sqlite.svg?branch=master
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[build-url]: https://travis-ci.org/stainless-steel/sqlite
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[documentation-img]: https://docs.rs/sqlite/badge.svg
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[documentation-url]: https://docs.rs/sqlite
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[package-img]: https://img.shields.io/crates/v/sqlite.svg
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[package-url]: https://crates.io/crates/sqlite
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