How do you handle TypeORM migrations in a NestJS project?

Q: How do you handle TypeORM migrations in a NestJS project?

// datasource.ts — separate file for TypeORM CLI export const AppDataSource = new DataSource({ type: 'postgres', host: process.env.DB_HOST, entities: ['src/**/*.entity.ts'], migrations: ['src/migrations/*.ts'], }); // package.json scripts // "migration:generate": "typeorm-ts-node-commonjs migration:generate src/migrations/Migration -d src/datasource.ts" // "migration:run": "typeorm-ts-node-commonjs migration:run -d src/datasource.ts" // "migration:revert": "typeorm-ts-node-commonjs migration:revert -d src/datasource.ts" // Generated migration — always implement down() export class AddUserNameColumn1234567890 implements MigrationInterface { async up(queryRunner: QueryRunner): Promise { await queryRunner.addColumn('users', new TableColumn({ name: 'name', type: 'varchar', isNullable: true, })); } async down(queryRunner: QueryRunner): Promise { await queryRunner.dropColumn('users', 'name'); } } Never use synchronize: true in production — it can drop columns and tables destructively. Keep a separate datasource.ts for the TypeORM CLI so it works independently of the NestJS app module. Always implement down() — rollbacks are critical for safe deployments and hotfixes. Commit all migration files to version control — they are the source of truth for schema history. Use migrationsRun: true in the NestJS TypeORM config to auto-apply pending migrations on startup.

Difficulty: 5/10

migration generation, migration execution, migration strategy

Create a separate datasource.ts file for the TypeORM CLI that does not depend on the NestJS app module. Generate migrations with migration:generate, apply with migration:run, and roll back with migration:revert. Never use synchronize: true in production — use migrations exclusively.

Separate datasource and migration workflow

Migration workflow best practices:

1
Never use synchronize: true in production — it can drop columns and tables destructively.
2

How do you handle TypeORM migrations in a NestJS project?

Difficulty: 5/10

migration generation, migration execution, migration strategy

Create a separate datasource.ts file for the TypeORM CLI that does not depend on the NestJS app module. Generate migrations with migration:generate, apply with migration:run, and roll back with migration:revert. Never use synchronize: true in production — use migrations exclusively.

Separate datasource and migration workflow

Migration workflow best practices:

1
Never use synchronize: true in production — it can drop columns and tables destructively.
2

How do you handle TypeORM migrations in a NestJS project?

Create a separate datasource.ts file for the TypeORM CLI that does not depend on the NestJS app module. Generate migrations with migration:generate, apply with migration:run, and roll back with migration:revert. Never use synchronize: true in production — use migrations exclusively.

How do you handle TypeORM migrations in a NestJS project?

Create a separate datasource.ts file for the TypeORM CLI that does not depend on the NestJS app module. Generate migrations with migration:generate, apply with migration:run, and roll back with migration:revert. Never use synchronize: true in production — use migrations exclusively.

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