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SQLiteMigrations

SQLiteMigrations is a .NET Standard Library for use with SQLite-net that allows you to manage database migrations using the PRAGMA option

Dependencies

SQLite-net

NuGet Installation

Install Vitvov.SQLiteMigrations from NuGet.

Usage

Create a database connection

Let's say you have a database table

[Table("record")]
public class RecordEntity
{
    [PrimaryKey, AutoIncrement]
    [Column("id")]
    public long Id { get; set; }

    [Column("startTime")]
    public DateTime StartTime { get; set; }

    [Column("endTime")]
    public DateTime EndTime { get; set; }
}

In order to create a database, you must create a class that implements SQLiteAsyncDatabase. You will have access to the public property Connection of type SQLiteAsyncConnection. In the CreateAsync() method, write the database creation script. Return null in the Migrations() method.

public class AppDatabase : SQLiteAsyncDatabase
{
    private const int DB_VERSION = 1;

    public AppDatabase(string path) : base(DB_VERSION, path)
    {
    }

    public override async Task CreateAsync()
    {
        await Connection.CreateTableAsync<RecordEntity>();
    }

    public override List<IMigration> Migrations()
    {
        return null;
    }
}

To access tables, use the Connection property. For example, you can add a property to your class

public class AppDatabase : SQLiteAsyncDatabase
{
    // some code ...
    public AsyncTableQuery<RecordEntity> RecordsTable => Connection.Table<RecordEntity>();
}

To start working with the AppDatabase, call

var dbPath = Path.Combine(FileSystem.AppDataDirectory, "db.sqlite");
var database = new AppDatabase(dbPath);
await database.ConnectAsync();
//usage
//database.Connection.Table<RecordEntity>()...

Add migrations

Let's say you want to add a new table

[Table("data")]
public class DataEntity
{
    [PrimaryKey, AutoIncrement]
    [Column("id")]
    public long Id { get; set; }

    [Column("pulse")]
    public int Pulse { get; set; }

    [Column("recordId")]
    public long RecordId { get; set; }
}

Let's create a migration for our database. Create a new migration class and implement the IMigration interface

public class Migration1To2 : IMigration
{
    public int OldVersion => 1;
    public int NewVersion => 2;

    public void Migrate(SQLiteConnection connection)
    {
        connection.CreateTable<DataEntity>();
    }
}

And also make a change to the database class

public class AppDatabase : SQLiteAsyncDatabase
{
    private const int DB_VERSION = 2; // <- change version from 1 to 2

    public AppDatabase(string path) : base(DB_VERSION, path)
    {
    }

    public override async Task CreateAsync()
    {
        await Connection.CreateTableAsync<RecordEntity>();
        await Connection.CreateTable<DataEntity>(); // <- add line
    }

    public override List<IMigration> Migrations()
    {
        // <- return the migration
        return new List<IMigration>
        {
            new Migration1To2()
        };
    }
}

One more example

Let's say you want to add a new field to the RecordEntity table

[Table("record")]
public class RecordEntity
{
    // some code...
    
    //  new property
    [Column("recorder")]
    public string RecorderName { get; set; }
}

Let's create a migration for our database

public class Migration2To3 : IMigration
{
    public int OldVersion => 2;
    public int NewVersion => 3;

    public void Migrate(SQLiteConnection connection)
    {
        connection.Execute("ALTER TABLE record ADD COLUMN recorder VARCHAR");
    }
}

And also make a change to the database class

public class AppDatabase : SQLiteAsyncDatabase
{
    private const int DB_VERSION = 3; // <- change version from 2 to 3

    public AppDatabase(string path) : base(DB_VERSION, path)
    {
    }

    public override async Task CreateAsync()
    {
        await Connection.CreateTableAsync<RecordEntity>();
        await Connection.CreateTable<DataEntity>();
    }

    public override List<IMigration> Migrations()
    {
        return new List<IMigration>
        {
            new Migration1To2(),
            new Migration2To3()// <- add new line
        };
    }
}

Using own SQLiteConnectionString

To use your own connection string, pass it to the base class constructor.

public class AppDatabase : SQLiteAsyncDatabase
{
    public AppDatabase(SQLiteConnectionString сonnectionString) : base(DB_VERSION, сonnectionString)
    {
    }
}
var options = new SQLiteConnectionString(databasePath);
var database = new AppDatabase(options);
await database.ConnectAsync();