Question

我正在尝试为我的查询确定更好的方法。我有两张桌子，一张是食谱，另一张是评论。目前，我有两个单独的查询来查找配方，然后找到与配方相关的评论。我有更好的方法吗？

RecipeController

module.exports = {
viewRecipe: function(req, res) {
    var recipeId = parseInt(req.params.id, 10);
    var recipeM = {};
    var reviewM = {};
    db.recipe.find({
        where: {
            id: recipeId
        }
    }).then(function(recipe) {
        recipeM = recipe.dataValues;
        recipeM.ingredients = recipe.ingredients.replace(/\s+/g, '').split(",");
        recipeM.instructions = recipe.instructions.split("\n");
    }, function (e) {
    });
    db.review.findAll({
        where: {
            recipeId: recipeId
        }
    }).then(function(review) {
        console.log(review);
        res.render('viewRecipe', { recipe: recipeM, review: review, categories: categoriesMain, title: recipeM.title });
    }, function(e) {

    });

},

Answer 1

如果您被允许使用ES6生成器，您可以从npm模块co

应用co.wrap

module.exports = {                                                                                                                        
viewRecipe: co.wrap(function*(req, res) {                                                                                                 
    var recipeId = parseInt(req.params.id, 10);                                                                                           
    var recipeM = {};                                                                                                                     
    var reviewM = {};                                                                                                                     
    var recipe = yield db.recipe.find({                                                                                                   
        where: {                                                                                                                          
            id: recipeId                                                                                                                  
        }                                                                                                                                 
    });                                                                                                                                   

    recipeM = recipe.dataValues;                                                                                                          
    recipeM.ingredients = recipe.ingredients.replace(/\s+/g, '').split(",");                                                              
    recipeM.instructions = recipe.instructions.split("\n");                                                                               

    var review = yield db.review.findAll({                                                                                                
        where: {                                                                                                                          
            recipeId: recipeId                                                                                                            
        }                                                                                                                                 
    });                                                                                                                                   

    console.log(review);                                                                                                                  
    res.render('viewRecipe', { recipe: recipeM, review: review, categories: categoriesMain, title: recipeM.title });                      
}).catch(function(e){                                                                                                                     

}),

Answer 2

如果您在食谱和评论之间建立了关系，我相信您可以使用Sequelize的包含选项，如下所示：

db.recipe
  .findById(req.params.id, {
    include: [{
      model: review
    }]
  })
  .then(function(recipe) {
     // your success code
  })
  .catch(function(err) {
     // you error code
  });

据我所知，include选项可用作左连接。此外，这应该会更好，因为只会在数据库上运行一个查询。

使用node.js查询查询

2 个答案: