Entity Framework Core Skill Sorcha uses EF Core 9+ with PostgreSQL (Npgsql) as the primary relational data store. The codebase implements a layered repository pattern with generic and specialized repositories, soft delete via query filters, and automatic migrations on startup. Quick Start Register DbContext with PostgreSQL // src/Common/Sorcha.Storage.EFCore/Extensions/EFCoreServiceExtensions.cs services . AddDbContext < WalletDbContext

( ( sp , options ) => { var dataSource = sp . GetRequiredService < NpgsqlDataSource

( ) ; options . UseNpgsql ( dataSource , npgsql => { npgsql . EnableRetryOnFailure ( maxRetryCount : 10 , maxRetryDelay : TimeSpan . FromSeconds ( 30 ) , errorCodesToAdd : null ) ; npgsql . MigrationsHistoryTable ( "__EFMigrationsHistory" , "wallet" ) ; } ) ; } ) ; Create a Migration

From project directory containing DbContext

dotnet ef migrations add InitialSchema --project src/Common/Sorcha.Wallet.Core --startup-project src/Services/Sorcha.Wallet.Service Apply Migrations Programmatically // Startup pattern used in Sorcha services var pending = await dbContext . Database . GetPendingMigrationsAsync ( ) ; if ( pending . Any ( ) ) await dbContext . Database . MigrateAsync ( ) ; Key Concepts Concept Usage Example DbContext Schema definition + change tracking WalletDbContext , TenantDbContext Repository Data access abstraction EFCoreRepository Soft Delete Query filter on DeletedAt .HasQueryFilter(e => e.DeletedAt == null) JSONB PostgreSQL JSON columns .HasColumnType("jsonb") ExecuteUpdate Bulk updates without loading ExecuteUpdateAsync(s => s.SetProperty(...)) Common Patterns Repository with Optional Eager Loading // src/Common/Sorcha.Wallet.Core/Repositories/EfCoreWalletRepository.cs public async Task < WalletEntity ?

GetByAddressAsync ( string address , bool includeAddresses = false ) { IQueryable < WalletEntity

query

_context . Wallets ; if ( includeAddresses ) query = query . Include ( w => w . Addresses ) ; return await query . AsNoTracking ( ) . FirstOrDefaultAsync ( w => w . Address == address ) ; } Soft Delete with Filter Bypass // Bypass query filter for admin operations var deleted = await _context . Wallets . IgnoreQueryFilters ( ) . FirstOrDefaultAsync ( w => w . Address == address ) ; See Also patterns - DbContext configuration, entity mapping, query optimization workflows - Migration commands, testing patterns, deployment