text: exports.up = function(knex, Promise) {
    return Promise.all([
      knex.schema.createTable('meetings', table => {
        table.increments('id').primary()
        table.dateTime('date')
        table.string('secret')
        table.string('summary_link')
        table.string('agenda_link')
        table.integer('group_id').references('groups.id').notNullable()
      }),
      knex.schema.createTable('groups', table => {
        table.increments('id')
        table.string('name')
        table.string('color')
      }),
      knex.schema.createTable('users', table => {
        table.string('id').primary()
      }),
      knex.schema.createTable('attendants', table => {
        table.increments('id')
        table.integer('meeting_id').references('meetings.id')
        table.string('user_id')
      })
    ])
  }
  
  exports.down = function(knex, Promise) {
    return Promise.all([
      knex.schema.dropTable('attendants'),
      knex.schema.dropTable('meetings'),
      knex.schema.dropTable('groups'),
      knex.schema.dropTable('users')
    ])
  }
  