Hi, i’m studying this lesson, following your hint i’ve written this code for the query chain:
const queryChain = (done) => {
const foodToSearch = "burrito";
Person.find({favoriteFoods: foodToSearch})
.sort({ name: -1 })
.limit(2)
.select({ age: 0 })
.exec(function(error, people) {
if(error) return console.log(error);
done(error, data)
});
};
there sure be something wrong, i don’t pass the test, hope you can lead me to the solution!
Also in the mongoose’s documentation can’t find model.sort 
Hello, buddy. You may use .sort({name: 1}) instead .sort({name -1}). Have fun! 
I’ve written this code:
Person.find({favoriteFoods: foodToSearch})
.sort({ name: 1 })
.limit(2)
.select({ age: 0 })
.exec(function(error, people) {
if(error) return console.error(error);
done(error, data)
});
};
but still doesn’t work, it gives me error. Hope for your help
As mentioned in the documentation, the .find() method applied on a Model returns a Query. So you should look into Query.sort() 
const queryChain = (done) => {
const foodToSearch = "burrito";
Person.find({favoriteFoods : foodToSearch})
.sort({name:1})
.limit(2)
.select({age:0})
.exec(function(err,data){
if(err) return console.log(err)
done(null, data)
});
};
Don’t know this will help or not , can you try the done() with null and data . done(null, data)
Thank you for your advices, i’m working on it 
I don’t know if the tests are buggy or not but in some cases when the tests say timed out try to re run it multiple times… it works for the 2nd or the 5th time
this is the only thing seems to work… as our code is correct but it seems that the most of the mongo and mongoose section tests are all buggy
Thanks, this worked for me
I believe the lesson suggests that you store the results in a variable for later execution through .exec(). Although the lesson teaches to use this syntax, async await with a Try & Catch block is more efficient. Below is the coding I used to solve this lesson. From my understanding it’s always good practice to return the data to the client but in this case there really isn’t one so I returned it in the console instead:
const queryChain = (done) => {
const foodToSearch = "burrito";
const findPerson =
Person
.find({favoriteFoods: foodToSearch})
.sort({name: 1})
.limit(2)
.select({age: 0})
.exec((err, data) => {
if(!err) {
done(null, data);
console.log(`Chained Successfully. Results: ${data}`)
} else {
console.log(err);
};
});
};I see that you were returning data not people
in the last line of code:
done(error, data - (should be “people” instead))
in the call back fir the .exec the variable data is used to represent errorless response with some values in in,
that is why he have to use data for now untill it is running within the .exec functional scope you can name the variable by any name you like , but one it is the scope , only it will be responsible for the outcome. as the second one is null.
and
oh alright, I got it. Thanks for clarifying. In that case, I think he had to use data in both places right? I was saying that the same values should be used in both places
yep, the tests fail for no apparent reason. Even if I copy paste the solution code provided, it doesn’t pass on the 11th exercise.
If you need help with your code please create a thread and post a link to your Replit or a GitHub repo with the code.
Not sure what solution code you are referring to. But there is nothing wrong with the tests, they work just fine for me with my own code and DB.
I have issues with the last challenge as well, I created this thread:
In
Person.find({favoriteFoods: foodToSearch})
replace foodToSearch with [foodToSearch] as it is an array of Strings type.
Also put in .sort( { name:1 }) instead of -1.
Final Code:
const queryChain = (done) => {
const foodToSearch = "burrito";
Person.find({ favoriteFoods: foodToSearch })
.sort({ name: 1 })
.limit(2)
.select({ age: 0 })
.exec(function(err, data) {
done(err,data);
});
};