freeCodeCamp/curriculum/challenges/english/05-apis-and-microservices/mongodb-and-mongoose/chain-search-query-helpers-...

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---
id: 587d7fb9367417b2b2512c12
title: Chain Search Query Helpers to Narrow Search Results
challengeType: 2
forumTopicId: 301533
dashedName: chain-search-query-helpers-to-narrow-search-results
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---
# --description--
If you dont pass the callback as the last argument to `Model.find()` (or to the other search methods), the query is not executed. You can store the query in a variable for later use. This kind of object enables you to build up a query using chaining syntax. The actual db search is executed when you finally chain the method `.exec()`. You always need to pass your callback to this last method. There are many query helpers, here we'll use the most commonly used.
# --instructions--
Modify the `queryChain` function to find people who like the food specified by the variable named `foodToSearch`. Sort them by `name`, limit the results to two documents, and hide their age. Chain `.find()`, `.sort()`, `.limit()`, `.select()`, and then `.exec()`. Pass the `done(err, data)` callback to `exec()`.
# --hints--
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Chaining query helpers should succeed
```js
(getUserInput) =>
$.ajax({
url: getUserInput('url') + '/_api/query-tools',
type: 'POST',
contentType: 'application/json',
data: JSON.stringify([
{ name: 'Pablo', age: 26, favoriteFoods: ['burrito', 'hot-dog'] },
{ name: 'Bob', age: 23, favoriteFoods: ['pizza', 'nachos'] },
{ name: 'Ashley', age: 32, favoriteFoods: ['steak', 'burrito'] },
{ name: 'Mario', age: 51, favoriteFoods: ['burrito', 'prosciutto'] }
])
}).then(
(data) => {
assert.isArray(data, 'the response should be an Array');
assert.equal(
data.length,
2,
'the data array length is not what expected'
);
assert.notProperty(
data[0],
'age',
'The returned first item has too many properties'
);
assert.equal(
data[0].name,
'Ashley',
'The returned first item name is not what expected'
);
assert.notProperty(
data[1],
'age',
'The returned second item has too many properties'
);
assert.equal(
data[1].name,
'Mario',
'The returned second item name is not what expected'
);
},
(xhr) => {
throw new Error(xhr.responseText);
}
);
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```
# --solutions--
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```js
/**
Backend challenges don't need solutions,
because they would need to be tested against a full working project.
Please check our contributing guidelines to learn more.
*/
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```