---

name: db-migrate description: Create database migration scripts following project patterns. Use when user mentions "migration", "add column", "alter table", "schema change", or "database update".

Database Migration

Create migration scripts for Neon PostgreSQL following project conventions.

Instructions

1. Read current schema:

   • prisma/schema.sql for table definitions
   • src/lib/db.ts for TypeScript interfaces

2. Create migration script in scripts/ directory:

   • Filename: <action>-<description>.mjs (e.g., add-views-column.mjs)
   • Use existing pattern from scripts/add-summary-column.mjs

3. Migration script template:

   Copyimport { neon } from '@neondatabase/serverless';
   import { config } from 'dotenv';
   import { fileURLToPath } from 'url';
   import { dirname, join } from 'path';
   
   const __filename = fileURLToPath(import.meta.url);
   const __dirname = dirname(__filename);
   
   config({ path: join(__dirname, '..', '.env.local') });
   
   const sql = neon(process.env.DATABASE_URL);
   
   async function migrate() {
     console.log('Running migration...');
   
     await sql`
       ALTER TABLE table_name
       ADD COLUMN IF NOT EXISTS column_name TYPE
     `;
   
     console.log('Migration complete!');
   }
   
   migrate().catch(console.error);
   

4. Update src/lib/db.ts:

   • Add new fields to relevant interface
   • Update query functions if needed

5. Update prisma/schema.sql:

   • Add new column to CREATE TABLE statement

Examples

• "Add a views column to articles"
• "Create migration for user preferences table"
• "Add index on published_at"

Guardrails

• ALWAYS use IF NOT EXISTS or IF EXISTS for safety
• NEVER use DROP TABLE without explicit confirmation
• Test migration on development database first
• Back up data before destructive operations: curl localhost:3000/api/admin/articles/export