sequelize-migrations

# Sequelize Migration Patterns

## Migration Basics

### File Structure
```
migrations/
├── 20240101000000-create-users.js
├── 20240101000001-create-orders.js
├── 20240102000000-add-status-to-users.js
└── 20240103000000-add-index-to-orders.js
```

### Basic Migration Template
```javascript
'use strict';

/** @type {import('sequelize-cli').Migration} */
module.exports = {
  async up(queryInterface, Sequelize) {
    // Forward migration
  },

  async down(queryInterface, Sequelize) {
    // Rollback migration
  },
};
```

## Creating Tables

### Basic Table Creation
```javascript
module.exports = {
  async up(queryInterface, Sequelize) {
    await queryInterface.createTable('users', {
      id: {
        type: Sequelize.BIGINT,
        primaryKey: true,
        autoIncrement: true,
      },
      email: {
        type: Sequelize.TEXT,
        allowNull: false,
        unique: true,
      },
      first_name: {
        type: Sequelize.TEXT,
        allowNull: false,
      },
      last_name: {
        type: Sequelize.TEXT,
        allowNull: false,
      },
      status: {
        type: Sequelize.TEXT,
        allowNull: false,
        defaultValue: 'active',
      },
      metadata: {
        type: Sequelize.JSONB,
        allowNull: false,
        defaultValue: {},
      },
      created_at: {
        type: Sequelize.DATE,
        allowNull: false,
        defaultValue: Sequelize.literal('NOW()'),
      },
      updated_at: {
        type: Sequelize.DATE,
        allowNull: false,
        defaultValue: Sequelize.literal('NOW()'),
      },
    });

    // Add indexes after table creation
    await queryInterface.addIndex('users', ['email'], { unique: true });
    await queryInterface.addIndex('users', ['status']);
    await queryInterface.addIndex('users', ['created_at']);
  },

  async down(queryInterface) {
    await queryInterface.dropTable('users');
  },
};
```

### Table with Foreign Keys
```javascript
module.exports = {
  async up(queryInterface, Sequelize) {