limbo_core::Value in Simulator for massive code reuse' from Pedro Muniz
This PR is a Drop-In replacement to the Predicate defined in the Simulator. Predicate is basically the same as our ast::Expr, but it supports a small number of the SQL expression syntax. By creating a NewType that wraps ast::Expr we can tap into our already mostly correctly defined parser structs. This change will enable us to easily add generation for more types of sql queries. I also added an ArbitraryFrom impl for ast::Expr that can be used in a freestyle way (for now) for differential testing. This PR also aims to implement Unary Operator logic similar to the Binary Operator logic we have for predicate. After this change we may need to adjust the Logic for how some assertions are triggered. <s>Sometimes the `Select-Select-Optimizer` property thinks that these two queries should return the same thing: ```sql SELECT (twinkling_winstanley.sensible_federations > x'66616e7461737469625e0f37879823db' AND twinkling_winstanley.sincere_niemeyer < -7428368947470022783) FROM twinkling_winstanley WHERE 1; SELECT * FROM twinkling_winstanley WHERE twinkling_winstanley.sensible_federations > x'66616e7461737469625e0f37879823db' AND twinkling_winstanley.sincere_niemeyer < -7428368947470022783; ``` However after running the shrunk plan manually, the simulator was incorrect in asserting that. Maybe this a bug a in the generation of such a query? Not sure yet. </s> <b>EDIT: The simulator was correctly catching a bug and I thought I was the problem. The bug was in `exec_if` and I fixed it in this PR.</b> I still need to expand the Unary Operator generation to other types of predicates. For now, I just implemented it for `SimplePredicate` as I'm trying to avoid to bloat even more this PR. <b>EDIT: I decided to just have one PR open for all the changes I'm making to make my life a bit easier and to avoid merge conflicts with my own branches that I keep spawning for new code.</b> PS: This should only be considered for merging after https://github.com/tursodatabase/limbo/pull/1619 is merged. Then, I will remove the draft status from this PR. Reviewed-by: Jussi Saurio <jussi.saurio@gmail.com> Closes #1674
Project Limbo
Limbo is a project to build the next evolution of SQLite.
Features and Roadmap
Limbo is a work-in-progress, in-process OLTP database engine library written in Rust that has:
- Asynchronous I/O support on Linux with
io_uring - SQLite compatibility [doc] for SQL dialect, file formats, and the C API
- Language bindings for JavaScript/WebAssembly, Rust, Go, Python, and Java
- OS support for Linux, macOS, and Windows
In the future, we will be also working on:
BEGIN CONCURRENTfor improved write throughput.- Indexing for vector search.
- Improved schema management including better
ALTERsupport and strict column types by default.
Getting Started
💻 Command Line
You can install the latest `limbo` release with:
curl --proto '=https' --tlsv1.2 -LsSf \
https://github.com/tursodatabase/limbo/releases/latest/download/limbo_cli-installer.sh | sh
Then launch the shell to execute SQL statements:
Limbo
Enter ".help" for usage hints.
Connected to a transient in-memory database.
Use ".open FILENAME" to reopen on a persistent database
limbo> CREATE TABLE users (id INT PRIMARY KEY, username TEXT);
limbo> INSERT INTO users VALUES (1, 'alice');
limbo> INSERT INTO users VALUES (2, 'bob');
limbo> SELECT * FROM users;
1|alice
2|bob
You can also build and run the latest development version with:
cargo run
🦀 Rust
cargo add limbo
Example usage:
let db = Builder::new_local("sqlite.db").build().await?;
let conn = db.connect()?;
let res = conn.query("SELECT * FROM users", ()).await?;
✨ JavaScript
npm i limbo-wasm
Example usage:
import { Database } from 'limbo-wasm';
const db = new Database('sqlite.db');
const stmt = db.prepare('SELECT * FROM users');
const users = stmt.all();
console.log(users);
🐍 Python
pip install pylimbo
Example usage:
import limbo
con = limbo.connect("sqlite.db")
cur = con.cursor()
res = cur.execute("SELECT * FROM users")
print(res.fetchone())
🐹 Go
- Clone the repository
- Build the library and set your LD_LIBRARY_PATH to include limbo's target directory
cargo build --package limbo-go
export LD_LIBRARY_PATH=/path/to/limbo/target/debug:$LD_LIBRARY_PATH
- Use the driver
go get github.com/tursodatabase/limbo
go install github.com/tursodatabase/limbo
Example usage:
import (
"database/sql"
_ "github.com/tursodatabase/limbo"
)
conn, _ = sql.Open("sqlite3", "sqlite.db")
defer conn.Close()
stmt, _ := conn.Prepare("select * from users")
defer stmt.Close()
rows, _ = stmt.Query()
for rows.Next() {
var id int
var username string
_ := rows.Scan(&id, &username)
fmt.Printf("User: ID: %d, Username: %s\n", id, username)
}
☕️ Java
We integrated Limbo into JDBC. For detailed instructions on how to use Limbo with java, please refer to the README.md under bindings/java.
Contributing
We'd love to have you contribute to Limbo! Please check out the contribution guide to get started.
FAQ
Is Limbo ready for production use?
Limbo is currently under heavy development and is not ready for production use.
How is Limbo different from Turso's libSQL?
Limbo is a project to build the next evolution of SQLite in Rust, with a strong open contribution focus and features like native async support, vector search, and more. The libSQL project is also an attempt to evolve SQLite in a similar direction, but through a fork rather than a rewrite.
Rewriting SQLite in Rust started as an unassuming experiment, and due to its incredible success, replaces libSQL as our intended direction. At this point, libSQL is production ready, Limbo is not - although it is evolving rapidly. As the project starts to near production readiness, we plan to rename it to just "Turso". More details here.
Publications
- Pekka Enberg, Sasu Tarkoma, Jon Crowcroft Ashwin Rao (2024). Serverless Runtime / Database Co-Design With Asynchronous I/O. In EdgeSys ‘24. [PDF]
- Pekka Enberg, Sasu Tarkoma, and Ashwin Rao (2023). Towards Database and Serverless Runtime Co-Design. In CoNEXT-SW ’23. [PDF] [Slides]
License
This project is licensed under the MIT license.
Contribution
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in Limbo by you, shall be licensed as MIT, without any additional terms or conditions.
Contributors
Thanks to all the contributors to Limbo!
