Introduction to RoomSharp

What is RoomSharp?

RoomSharp is a Room-inspired data layer for modern .NET that combines a Roslyn source generator, attribute-driven models, and lightweight database providers to produce zero-reflection DAOs, migrations, and schema builders. It supports SQLite, SQL Server, PostgreSQL, and MySQL while still letting you drop down to raw ADO.NET when needed.

Why RoomSharp?

Source-Generated DAOs

RoomSharp uses Roslyn source generators to emit fully compiled data access implementations at build time. This means:

• Zero runtime reflection overhead
• Type-safe query methods
• IDE auto-completion and IntelliSense support
• Compile-time error detection

Multi-Provider Runtime

Common abstractions over multiple database engines with tuned dialect helpers:

• SQLite - Lightweight, embedded database
• SQL Server - Enterprise-grade relational database
• PostgreSQL - Advanced open-source database
• MySQL/MariaDB - Popular open-source databases

High Performance

• IL-Based Mapping: Ultra-fast data reader to object mapping using IL generation
• Zero Allocations: Hot loops designed for minimal memory pressure
• Batch Insert Engine: Optimized bulk operations with prepared statement reuse
• 2-5x Faster: Benchmark results show significant performance improvements over alternatives

Rich Annotations

Express your database schema with intuitive attributes:

• [Entity] - Define table mappings
• [PrimaryKey] - Specify primary keys with auto-generation
• [Index] - Create database indexes
• [ForeignKey] - Define relationships
• [Embedded] & [Relation] - Handle complex object graphs
• [TypeConverter] - Custom type conversions

Core Architecture

RoomSharp consists of three main layers:

Quick Example

Here's a minimal example to get you started:

// 1. Define your entity
[Entity(TableName = "users")]
public class User
{
    [PrimaryKey(AutoGenerate = true)]
    public long Id { get; set; }
    
    [Unique]
    public required string Email { get; set; }
    public string? Name { get; set; }
}

// 2. Define your DAO
[Dao]
public interface IUserDao
{
    [Insert]
    long Insert(User user);
    
    [Query("SELECT * FROM users WHERE Email = :email")]
    Task<User?> FindByEmailAsync(string email);
}

// 3. Define your database
[Database(Version = 1, Entities = [typeof(User)])]
public abstract class AppDatabase(IDatabaseProvider provider) 
    : RoomDatabase(provider)
{
    public abstract IUserDao UserDao { get; }
}

// 4. Use it
var db = RoomDatabase.Builder<AppDatabaseImpl>()
    .UseSqlite("app.db")
    .Build();

var userId = db.UserDao.Insert(new User 
{ 
    Email = "john@example.com", 
    Name = "John" 
});

var user = await db.UserDao.FindByEmailAsync("john@example.com");

Next Steps

Now that you understand what RoomSharp is, let's get it installed and start building:

• Installation Guide - Set up RoomSharp in your project
• Entities - Learn how to define your data models
• DAO Interfaces - Create data access objects
• Benchmarks - See the performance numbers