Rusqlite Migration is a simple schema migration library for rusqlite using user_version instead of an SQL table to maintain the current schema version.
It aims for:
- simplicity: define a set of SQL statements. Just add more SQL statement to change the schema. No external CLI, no macro.
- performance: no need to add a table to be parsed, the user_version
field is at a fixed offset in the sqlite file format.
It works especially well with other small libraries complementing rusqlite, like serde_rusqlite.
Here, we define SQL statements to run with Migrations::new and run these (if necessary) with .to_latest().
```rust use rusqlite::{params, Connection}; use rusqlite_migration::{Migrations, M};
// 1️⃣ Define migrations let migrations = Migrations::new(vec![ M::up("CREATE TABLE friend(name TEXT NOT NULL);"), // In the future, add more migrations here: //M::up("ALTER TABLE friend ADD COLUMN email TEXT;"), ]);
let mut conn = Connection::openinmemory().unwrap();
// Apply some PRAGMA, often better to do it outside of migrations conn.pragmaupdate(None, "journalmode", &"WAL").unwrap();
// 2️⃣ Update the database schema, atomically migrations.to_latest(&mut conn).unwrap();
// 3️⃣ Use the database 🥳 conn.execute("INSERT INTO friend (name) VALUES (?1)", params!["John"]) .unwrap(); ```
Please see the examples folder for more, in particular:
- migrations with multiple SQL statements (using for instance r#"…"
or include_str!(…)
)
- use of lazy_static
- migrations to previous versions (downward migrations)
I’ve also made a cheatsheet of SQLite pragma for improved performance and consistency.
To test that the migrations are working, you can add this in your test module:
```rust
fn migrationstest() { assert!(MIGRATIONS.validate().isok()); } ```
Contributions (documentation or code improvements in particular) are welcome, see contributing!
I would like to thank all the contributors, as well as the authors of the dependencies this crate uses.