Sequelize，检查行的存在并返回boolean。

Posted 2021-03-19

请你帮忙

我如何通过Sequelize实现一个请求'SELECT EXISTS(SELECT 1 FROM Followers WHERE follower_id = 100);'，并在一个单独的字段中显示结果？

像这样

await Followers.findAll({
  where: { user_id: userId },
  include: [
     {
      model: Followers,
      as: 'isSubscribed',
      ...
      },
    },
  ]

答案

做这样的事情

let followersCount = Followers.count({ where: {follower_id: 100} })

if(followersCount > 0){
  //EXISTS, Do Something
}
else{
   //Does not exist
 }