Migrations

Database migrations using Kysely.

Note: Migrations are optional. You can use Kysely for database operations without migrations. The schema file is also optional but recommended for LLM-assisted development and team collaboration.

Commands

Terminal window
# Create a new migration
npx kysely migrate:make my_migration_name


# Run all pending migrations
npm run migrate

Migration Example

import { Kysely, sql, ColumnDefinitionBuilder } from 'kysely';


export async function up(db: Kysely<any>): Promise<void> {
  await db.schema
    .createTable('posts')
    .addColumn('id', 'integer', (col: ColumnDefinitionBuilder) =>
      col.primaryKey().autoIncrement())
    .addColumn('uuid', 'varchar(255)', (col: ColumnDefinitionBuilder) =>
      col.notNull())
    .addColumn('created_at', 'timestamp', (col: ColumnDefinitionBuilder) =>
      col.notNull().defaultTo(sql`CURRENT_TIMESTAMP`))
    .addColumn('user_id', 'varchar(255)', (col: ColumnDefinitionBuilder) =>
      col.references('user.id').onDelete('set null'))
    .addColumn('title', 'varchar(255)')
    .addColumn('content', 'text')
    .addColumn('deleted_at', 'timestamp')
    .addColumn('updated_at', 'timestamp')
    .execute();
}


export async function down(db: Kysely<any>): Promise<void> {
  await db.schema.dropTable('posts').ifExists().execute();
}

Adding a Column

export async function up(db: Kysely<any>): Promise<void> {
  await db.schema
    .alterTable('posts')
    .addColumn('status', 'varchar(255)')
    .execute();
}

Workflow

  1. Create migration: npx kysely migrate:make add_status_to_posts
  2. Edit the migration file in ./migrations/
  3. Run migration: npm run migrate
  4. Update schema in ./src/config/schema.ts

Resources