old_contents: 
  exports.up = function(knex, Promise) {
    return knex.schema.createTable('pages', function (table) {
      table.increments('id').primary()
      table.string('title')
      table.text('body', 'longtext')
      table.string('status')
      table.dateTime('published_date')
    })
  };
  
  exports.down = function(knex, Promise) {
    return knex.schema.dropTable('pages')
  };
  
new_contents: 
  exports.up = function (knex, Promise) {
    return knex.schema.createTable('pages', function (table) {
      table.increments('id').primary()
      table.string('type')
      table.string('title')
      table.string('slug').unique()
      table.integer('author').unsigned()
      table.foreign('author').references('users.id')
      table.text('body', 'longtext')
      table.string('status')
      table.dateTime('published_date')
    })
  }
  
  exports.down = function (knex, Promise) {
    return knex.schema.dropTable('pages')
  }
  
subject: Add status, author and slug column to pages migration file