LiteDB - A .NET NoSQL Document Store in a single data file

LiteDB is a small, fast and lightweight .NET NoSQL embedded database.

• Serverless NoSQL Document Store
• Simple API, similar to MongoDB
• 100% C# code for .NET 4.5 / NETStandard 1.3/2.0 in a single DLL (less than 450kb)
• Thread-safe
• ACID with full transaction support
• Data recovery after write failure (WAL log file)
• Datafile encryption using DES (AES) cryptography This implemention is currently not secure, DO NOT USE.
• Map your POCO classes to BsonDocument using attributes or fluent mapper API
• Store files and stream data (like GridFS in MongoDB)
• Single data file storage (like SQLite)
• Index document fields for fast search
• LINQ support for queries
• SQL-Like commands to access/transform data
• LiteDB Studio - Nice UI for data access
• Open source and free for everyone - including commercial use
• Install from NuGet: Install-Package LiteDB

New v5

• New storage engine
• No locks for read operations (multiple readers)
• Write locks per collection (multiple writers)
• Internal/System collections
• New SQL-Like Syntax
• New query engine (support projection, sort, filter, query)
• Partial document load (root level)
• and much, much more!

Lite.Studio

New UI to manage and visualize your database:

Documentation

Visit the Wiki for full documentation. For simplified chinese version, check here.

LiteDB Community

Help LiteDB grow its user community by answering this simple survey

How to use LiteDB

A quick example for storing and searching documents:

// Create your POCO class
public class Customer
{
    public int Id { get; set; }
    public string Name { get; set; }
    public int Age { get; set; }
    public string[] Phones { get; set; }
    public bool IsActive { get; set; }
}

// Open database (or create if doesn't exist)
using(var db = new LiteDatabase(@"MyData.db"))
{
    // Get customer collection
    var col = db.GetCollection<Customer>("customers");

    // Create your new customer instance
    var customer = new Customer
    { 
        Name = "John Doe", 
        Phones = new string[] { "8000-0000", "9000-0000" }, 
        Age = 39,
        IsActive = true
    };

    // Create unique index in Name field
    col.EnsureIndex(x => x.Name, true);

    // Insert new customer document (Id will be auto-incremented)
    col.Insert(customer);

    // Update a document inside a collection
    customer.Name = "Joana Doe";

    col.Update(customer);

    // Use LINQ to query documents (with no index)
    var results = col.Find(x => x.Age > 20);
}

BSON serialization

If you need direct access to raw BSON, BsonSerializer exposes overloads that write into caller-supplied Memory<byte> or IBufferWriter<byte> instances. This allows applications to reuse buffers from pools without forcing an intermediate array allocation. The Memory<byte> must be backed by a managed array. The IBufferWriter<byte> overload is available in the net8.0 and net10.0 builds, but is omitted from the netstandard2.0 API.

var writer = new ArrayBufferWriter<byte>();
var written = BsonSerializer.Serialize(document, writer);

// written now contains the BSON length and writer.WrittenSpan holds the bytes

Using fluent mapper and cross document reference for more complex data models

// DbRef to cross references
public class Order
{
    public ObjectId Id { get; set; }
    public DateTime OrderDate { get; set; }
    public Address ShippingAddress { get; set; }
    public Customer Customer { get; set; }
    public List<Product> Products { get; set; }
}        

// Configure the global template. Mapper-less databases clone this configuration.
var mapper = BsonMapper.Global;

// "Products" and "Customer" are from other collections (not embedded document)
mapper.Entity<Order>()
    .DbRef(x => x.Customer, "customers")   // 1 to 1/0 reference
    .DbRef(x => x.Products, "products")    // 1 to Many reference
    .Field(x => x.ShippingAddress, "addr"); // Embedded sub document
            
using(var db = new LiteDatabase("MyOrderDatafile.db"))
{
    var orders = db.GetCollection<Order>("orders");
        
    // When query Order, includes references
    var query = orders
        .Include(x => x.Customer)
        .Include(x => x.Products) // 1 to many reference
        .Find(x => x.OrderDate <= DateTime.Now);

    // Each instance of Order will load Customer/Products references
    foreach(var order in query)
    {
        var name = order.Customer.Name;
        ...
    }
}

Where to use?

• Desktop/local small applications
• Application file format
• Small web sites/applications
• One database per account/user data store

Plugins

• A GUI viewer tool: https://github.com/falahati/LiteDBViewer (v4)
• A GUI editor tool: https://github.com/JosefNemec/LiteDbExplorer (v4)
• Lucene.NET directory: https://github.com/sheryever/LiteDBDirectory
• LINQPad support: https://github.com/adospace/litedbpad
• F# Support: https://github.com/Zaid-Ajaj/LiteDB.FSharp (v4)
• UltraLiteDB (for Unity or IOT): https://github.com/rejemy/UltraLiteDB
• OneBella - cross platform (windows, macos, linux) GUI tool : https://github.com/namigop/OneBella
• LiteDB Studio - Fork of OneBella with bug fixes, updates and migrated to C# - https://github.com/MelnikovIG/LiteDB.Studio.Avalonia
• LiteDB.Migration: Framework that makes schema migrations easier: https://github.com/JKamsker/LiteDB.Migration/

Changelog

Change details for each release are documented in the release notes.

Code Signing

LiteDB is digitally signed courtesy of SignPath