LightDB Storage Engine 🚀

A high-performance TypeScript database storage layer with WAL (Write-Ahead Logging), indexes, and transaction support.

Features ✨

• High Performance: Optimized for speed with batch writing and columnar storage
• Transaction Support: ACID-compliant operations
• Indexing: B+ tree indexes for fast querying
• Write-Ahead Logging: Ensures data durability
• Recovery: Automatic recovery from crashes
• Memory-Mapped Files: Efficient I/O operations
• TypeScript Ready: Full TypeScript support with type definitions

Installation 📦

pnpm add @yydb/light-db

Quick Start 🚀

import { LightDB } from '@yydb/light-db';

// Initialize the database
const db = await LightDB.open('./mydb');

// Create a collection
const users = db.collection('users');

// Insert a document
await users.insert({ id: 1, name: 'John Doe', email: '[email protected]' });

// Find a document
const user = await users.findOne({ id: 1 });
console.log(user); // { id: 1, name: 'John Doe', email: '[email protected]' }

// Update a document
await users.update({ id: 1 }, { $set: { name: 'John Smith' } });

// Delete a document
await users.delete({ id: 1 });

// Close the database
await db.close();

API Reference 📚

LightDB Class

open(path: string): Promise<LightDB>

Opens an existing database or creates a new one at the specified path.

collection(name: string): Collection

Returns a collection with the given name. Creates it if it doesn't exist.

transaction(): Promise<Transaction>

Starts a new transaction.

close(): Promise<void>

Closes the database connection.

Collection Class

insert(document: Document): Promise<void>

Inserts a new document into the collection.

find(query: Query): Promise<Document[]>

Finds all documents matching the query.

findOne(query: Query): Promise<Document | null>

Finds the first document matching the query.

update(query: Query, update: Update): Promise<number>

Updates documents matching the query and returns the number of updated documents.

delete(query: Query): Promise<number>

Deletes documents matching the query and returns the number of deleted documents.

createIndex(field: string): Promise<void>

Creates an index on the specified field for faster queries.

Transaction Class

commit(): Promise<void>

Commits the transaction.

rollback(): Promise<void>

Rolls back the transaction.

Performance Features ⚡

Batch Writing

LightDB uses batch writing to optimize disk I/O operations, significantly improving write performance for bulk operations.

Columnar Storage

For certain data types, LightDB uses columnar storage to reduce disk space and improve query performance.

Memory-Mapped Files

LightDB uses memory-mapped files for efficient I/O operations, reducing the overhead of traditional file I/O.

Architecture 🏗️

LightDB consists of several key components:

1. Storage Engine: Manages the physical storage of data
2. WAL (Write-Ahead Log): Ensures data durability and supports recovery
3. Index Manager: Manages B+ tree indexes for fast querying
4. Collection Layer: Provides a document-oriented API
5. Transaction Manager: Handles ACID-compliant transactions

Recovery 🔄

LightDB automatically recovers from crashes using the WAL. When the database is opened after a crash, it replays the WAL to restore the database to a consistent state.

Contributing 🤝

Contributions are welcome! Please feel free to submit a Pull Request.

License 📄

LightDB is licensed under the MPL-2.0 License. See the LICENSE file for details.