LottaDB 4.0.0

LottaDB

LottaDB is a .NET library that makes it easy to store any POCO in Azure Table Storage with full Lucene search, all with the goodness of LINQ. No schema required -- just define a class and go.

• A lotta power, a little work. Store any C# class with zero attributes. All properties are automatically queryable and searchable.
• A lotta bang for a little buck. Table Storage is the cheapest durable storage in Azure. LottaDB adds Lucene so you get rich queries without the rich pricing.
• A lotta LINQ. GetManyAsync<T>() and Search<T>(), .Where(), .OrderBy() etc.
• A lotta fidelity. Full JSON roundtrip. Lists, dictionaries, nested objects -- everything survives.
• A lotta views. On<T> triggers build materialized views with plain C#.
• A lotta tenants. One catalog per tenant with multiple databases. Natural isolation, simple cleanup.
• A lotta nothing to operate. Table Storage is serverless. Lucene runs in-process.
• A lotta schema safety. Schema changes are detected automatically -- Lucene index is rebuilt on startup.
• A lotta concurrency. ChangeAsync<T>() provides atomic read-modify-write with optimistic concurrency and automatic retry.

Sweet spot

LottaDB is ideal for per-user or per-tenant workloads -- think user profiles, settings, activity feeds, personal knowledge bases, mailboxes, or per-project data. Thousands of objects per tenant, thousands of tenants per deployment.

Installation

dotnet add package LottaDB

Quick Start -- Just Store a lotta objects

Just define a class. No attributes, no base classes, no interfaces:

public class Actor
{
    public string Username { get; set; } = "";
    public string DisplayName { get; set; } = "";
    public string AvatarUrl { get; set; } = "";
}

Create a catalog, register the type, and start storing:

var catalog = new LottaCatalog("myapp", "<your Azure Storage connection string>");
var db = await catalog.GetDatabaseAsync("default");

// Save -- a unique key (ULID) is auto-generated
var actor = new Actor { Username = "alice", DisplayName = "Alice" };
await db.SaveAsync(actor);
var key = actor.GetKey();  // e.g. "01JKX3Q7..."

// Point read by key
var loaded = await db.GetAsync<Actor>(key);

// Search -- all properties are automatically queryable
var found = db.Search<Actor>()
    .Where(a => a.DisplayName == "Alice")
    .ToList();

That's it. No key attribute needed -- a ULID is assigned automatically. Every property on your class is automatically:

• Stored as full-fidelity JSON in table storage
• Indexed in Lucene for fast search
• Queryable via LINQ expressions and full-text search

Fine-Tuning with Attributes

When you need more control, attributes let you specify keys, indexing behavior, and exclusions:

public class Note
{
    [Key]                                    // explicit key property
    public string NoteId { get; set; } = "";

    [Queryable(QueryableMode.NotAnalyzed)]   // exact match only
    public string AuthorId { get; set; } = "";

    [Queryable]                              // full-text search
    public string Content { get; set; } = "";

    [NotQueryable]                           // exclude from indexing (e.g., large payloads)
    public string RawHtml { get; set; } = "";

    public DateTimeOffset Published { get; set; }
    public List<string> Tags { get; set; } = new();
}

Concurrency

ChangeAsync<T>() provides safe read-modify-write with automatic retry on conflict:

await db.ChangeAsync<Actor>("alice", actor =>
{
    actor.DisplayName = "Alice Updated";
});

Multiple concurrent writers on the same key are handled correctly -- ETag-based optimistic concurrency ensures no updates are lost.

Storage Providers

LottaDB works with Azure Table Storage out of the box. For local development and testing, install a provider package:

// Local development with SQLite
var catalog = new LottaCatalog("myapp", catalog => catalog.UseSQLite(@"C:\data"));

// Unit tests with in-memory storage
var catalog = new LottaCatalog("myapp", catalog => catalog.UseMemory());

Documentation

Full documentation is available in the wiki: