Database Support

DataSmith supports external databases through a pluggable provider system.

Instead of hardcoding a specific database engine, DataSmith communicates with databases through the IDatabase interface. This allows you to switch between storage backends without changing your model code.

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🧠 Overview

Database-backed models use ModelValueType.DB.

These models:

• Persist data outside of memory
• Can execute queries through a database provider
• Support large datasets
• Enable server-backed or persistent storage
• Are independent of a specific SQL implementation

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🏗️ Enabling Database Models

Mark your model with ModelValueType.DB.

using Baruah.DataSmith;
 
[GameModel(ModelValueType.DB)]
public class AccountData
{
[PrimaryKey]
public int AccountId;
 
    public string Username;
    public int Coins;
}

Generated models will use the active database provider for storage and queries.

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🔌 Database Provider System

DataSmith communicates with databases using the IDatabase interface.

A provider implements this interface and executes commands against a specific backend.

Example Interface

public interface IDatabase
{
    IEnumerable<T> Query<T>(string commandText);
    int Execute(string commandText);
}

The exact interface may vary depending on the provider implementation.

⚙️ Configuring a Provider

The active database provider is configured through the DataContext.

DataContext.Database = new SqliteDatabase(connectionString);

Once configured, all DB models will use this provider automatically.

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🧪 Built-In SQLite Support

DataSmith can work with Mono.Data.Sqlite when available.

SQLite is ideal for:

• Local save data
• Offline applications
• Prototyping
• Small to medium datasets

Requirements

• Mono.Data.Sqlite.dll present in the project
• Compatible Unity scripting backend

Custom Database Providers

You can implement support for any database system by creating your own provider.

Example: Custom Provider

public class MyDatabase : IDatabase
{
    public IEnumerable<T> Query<T>(string commandText)
    {
    // Execute query and map results
    }
 
    public int Execute(string commandText)
    {
        // Execute non-query command
    }
}

Then register it:

DataContext.Database = new MyDatabase();

DataContext.Database = new MyDatabase();

🔎 Database Queries

For DB models, generated queries may be translated into database commands instead of in-memory filtering.

Example usage:

var richPlayers =
    DataContext.Get<AccountDataModel>()
        .Query()
        .CoinsGreaterThan(1000)
        .Execute();

The provider determines how this query is executed.

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💾 Persistence Behavior

Unlike in-memory models:

• Data is stored externally
• Changes may be committed immediately or batched
• Behavior depends on the provider implementation