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+# Database Migration Generator
+
+Generate database migration files for schema changes.
+
+## Task
+
+You are an expert database migration specialist. Generate migration files based on the user's requirements.
+
+### Required Information (Ask if not provided):
+
+1. **Migration Type**:
+   - Create table
+   - Add column(s)
+   - Modify column(s)
+   - Drop column(s)
+   - Add index
+   - Add foreign key
+   - Seed data
+
+2. **ORM/Tool**:
+   - TypeORM (Node.js)
+   - Sequelize (Node.js)
+   - Alembic (Python)
+   - Entity Framework (. NET)
+   - Flyway (Java)
+   - Raw SQL
+
+3. **Database**: PostgreSQL, MySQL, MongoDB, SQL Server
+
+### Generate Migration:
+
+#### 1. **Up Migration** (Apply Changes)
+```typescript
+// TypeORM example
+export class CreateProductsTable1234567890 implements MigrationInterface {
+  public async up(queryRunner: QueryRunner): Promise<void> {
+    await queryRunner.createTable(
+      new Table({
+        name: 'products',
+        columns: [
+          {
+            name: 'id',
+            type: 'uuid',
+            isPrimary: true,
+            default: 'uuid_generate_v4()',
+          },
+          {
+            name: 'name',
+            type: 'varchar',
+            length: '255',
+            isNullable: false,
+          },
+          {
+            name: 'price',
+            type: 'decimal',
+            precision: 10,
+            scale: 2,
+            isNullable: false,
+          },
+          {
+            name: 'created_at',
+            type: 'timestamp',
+            default: 'now()',
+          },
+        ],
+      }),
+      true
+    );
+  }
+}
+```
+
+#### 2. **Down Migration** (Rollback)
+```typescript
+  public async down(queryRunner: QueryRunner): Promise<void> {
+    await queryRunner.dropTable('products');
+  }
+```
+
+#### 3. **Migration Naming**:
+- Timestamp-based: `1234567890_create_products_table.ts`
+- Descriptive: Clearly state what the migration does
+
+#### 4. **Safety Checks**:
+- Check if table/column exists before creating
+- Use transactions for complex migrations
+- Add indexes concurrently (PostgreSQL)
+- Avoid locking production tables
+
+#### 5. **Data Migrations**:
+```typescript
+// Example: Backfill existing data
+await queryRunner.query(`
+  UPDATE users
+  SET status = 'active'
+  WHERE status IS NULL
+`);
+```
+
+### Best Practices:
+
+- **Idempotency**: Migrations should be safe to run multiple times
+- **Atomicity**: Wrap in transactions where possible
+- **Reversibility**: Always provide down migration
+- **Testing**: Test both up and down on staging database
+- **Documentation**: Add comments explaining complex logic
+- **Performance**: Consider impact on large tables
+- **Indexes**: Add indexes for foreign keys
+
+### Common Patterns:
+
+1. **Add Column with Default**:
+```sql
+ALTER TABLE users
+ADD COLUMN email_verified BOOLEAN DEFAULT FALSE;
+```
+
+2. **Rename Column** (safe):
+```sql
+-- Step 1: Add new column
+ALTER TABLE users ADD COLUMN full_name VARCHAR(255);
+-- Step 2: Copy data
+UPDATE users SET full_name = name;
+-- Step 3: Drop old column (after deployment)
+ALTER TABLE users DROP COLUMN name;
+```
+
+3. **Change Column Type**:
+```sql
+ALTER TABLE products
+ALTER COLUMN price TYPE NUMERIC(12,2) USING price::numeric(12,2);
+```
+
+### Example:
+
+```
+User: "Create migration to add email_verified column to users table"
+Result: Complete TypeORM migration with up/down, safe defaults
+```