AgentSkillsCN

NestJS Database

在数据访问模式、扩展性、迁移操作以及 ORM 选型方面的规范。

SKILL.md
--- frontmatter
name: NestJS Database
description: Data access patterns, Scaling, Migrations, and ORM selection.
metadata:
  labels: [nestjs, database, typeorm, prisma, mongodb]
  triggers:
    files: ['**/*.entity.ts', 'prisma/schema.prisma']
    keywords: [TypeOrmModule, PrismaService, MongooseModule, Repository]

NestJS Database Standards

Priority: P0 (FOUNDATIONAL)

Database integration patterns and ORM standards for NestJS applications.

Selection Strategy

See references/persistence_strategy.md for database selection matrix and scaling patterns (Connection Pooling, Sharding).

Patterns

  • •Repository Pattern: Isolate database logic.
    • •TypeORM: Inject @InjectRepository(Entity).
    • •Prisma: Create a comprehensive PrismaService.
  • •Abstraction: Services should call Repositories, not raw SQL queries.

Configuration (TypeORM)

  • •Async Loading: Always use TypeOrmModule.forRootAsync to load secrets from ConfigService.
  • •Sync: Set synchronize: false in production; use migrations instead.

Migrations

  • •Never use synchronize: true in production.
  • •Execution: Run via init container or CD step.
  • •Zero-Downtime: Use Expand-Contract pattern (Add -> Backfill -> Drop).
  • •Seeding: Use factories for dev data; only static dicts for prod.

Best Practices

  1. •Pagination: Mandatory. Use limit/offset or cursor-based pagination.
  2. •Indexing: Define indexes in code (decorators/schema) for frequently filtered columns (where, order by).
  3. •Transactions: Use QueryRunner (TypeORM) or $transaction (Prisma) for all multi-step mutations to ensure atomicity.