场景是博客 常见一个博客，会选择一个类别，当编辑保存的时候会判断类别是否变了，如果变了，就将以前的类别-1，新选择的类别+1，然后我就碰到问题了。。

更新博客源码：

exports.update = function(req, res) {
  var id = req.body.id;
  var title = req.body.title;
  var content = req.body.content;
  var oldCategoryId = req.body.oldCategoryId;
  var categoryId = req.body.categoryId;
  var isYuanChuang = req.body.isYuanChuang;
  var img = req.body.img;
  async.series({
    upload: function(next) {
      if (req.file) {
        var key = req.file.filename;
        var localFile = req.file.path;
        qiniuupload.uploadFile(key, localFile, function(err, ret) {
          if (err) {
            console.log(err);
          } else {
            img = CONFIG.qn_access.origin + "/" + ret.key;
            //删除本地文件
            fs.unlinkSync(localFile);
            next();
          }
        })
      } else {
        next();
      }
    },
    save: function(next) {
      Blog.update({
        title: title,
        content: content,
        updateAt: Date.now(),
        categoryId: categoryId,
        isYuanChuang: isYuanChuang,
        img: img
      }, {
        where: {
          id: id
        }
      }).then(function(result) {
        next();
      });
    }
  }, function(err, result) {
    if (oldCategoryId != categoryId) {
      //修改前的类别-1
      Common.updateBlogCount(oldCategoryId, false);
      //修改后的类别+1
      Common.updateBlogCount(categoryId, true);
    }
    res.redirect("/admin/blog/list");
  });
};

common.js里的updateBlogCount()方法

//修改类别里博客数量
//action == true ++ false --
exports.updateBlogCount = function(categoryId, action) {
  Category.findOne({
    id: categoryId
  }).then(function(result) {
    console.log(result.id, result.name, result.blogCount, categoryId);
    var count = 0;
    if (action == true) {
      count = result.blogCount + 1;
    } else {
      count = result.blogCount - 1;
    }
    Category.update({
      blogCount: count
    }, {
      where: {
        id: categoryId
      }
    }).then(function() {});
  });
};

updateBlogCount()方法里的console.log(result.id, result.name, result.blogCount, categoryId);打印出来的数据分别是：

6 'java' 1 '6'
6 'java' 1 '7'

categoryId分别是6，7，可查询出来的类别对象确实id为6的数据，求解这是为啥？