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
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---
## Description
<section id='description'>
fix(curriculum) Replace <code> with <blockquote>for code sections (#35442) * fix: reformatted code and moved instructions * fix: replaced code with blockquotes * Update curriculum/challenges/english/05-apis-and-microservices/mongodb-and-mongoose/chain-search-query-helpers-to-narrow-search-results.english.md Co-Authored-By: RandellDawson <5313213+RandellDawson@users.noreply.github.com> * Update curriculum/challenges/english/05-apis-and-microservices/mongodb-and-mongoose/install-and-set-up-mongoose.english.md Co-Authored-By: RandellDawson <5313213+RandellDawson@users.noreply.github.com> * Update curriculum/challenges/english/05-apis-and-microservices/mongodb-and-mongoose/create-a-model.english.md Co-Authored-By: RandellDawson <5313213+RandellDawson@users.noreply.github.com> * fix: made a few recommended changes of text * fix: moved </blockquote> to new line Co-Authored-By: RandellDawson <5313213+RandellDawson@users.noreply.github.com> * fix: removed extra space Co-Authored-By: RandellDawson <5313213+RandellDawson@users.noreply.github.com> * Update curriculum/challenges/english/05-apis-and-microservices/mongodb-and-mongoose/chain-search-query-helpers-to-narrow-search-results.english.md Co-Authored-By: RandellDawson <5313213+RandellDawson@users.noreply.github.com> * Update curriculum/challenges/english/05-apis-and-microservices/mongodb-and-mongoose/create-a-model.english.md Co-Authored-By: RandellDawson <5313213+RandellDawson@users.noreply.github.com> * fix: added the word The before code tag section
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If you dont pass the callback as the last argument to <code>Model.find()</code> (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 <code>.exec()</code>. You always need to pass your callback to this last method. There are many query helpers, here well use the most famous ones.
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</section>
## Instructions
<section id='instructions'>
fix(curriculum) Replace <code> with <blockquote>for code sections (#35442) * fix: reformatted code and moved instructions * fix: replaced code with blockquotes * Update curriculum/challenges/english/05-apis-and-microservices/mongodb-and-mongoose/chain-search-query-helpers-to-narrow-search-results.english.md Co-Authored-By: RandellDawson <5313213+RandellDawson@users.noreply.github.com> * Update curriculum/challenges/english/05-apis-and-microservices/mongodb-and-mongoose/install-and-set-up-mongoose.english.md Co-Authored-By: RandellDawson <5313213+RandellDawson@users.noreply.github.com> * Update curriculum/challenges/english/05-apis-and-microservices/mongodb-and-mongoose/create-a-model.english.md Co-Authored-By: RandellDawson <5313213+RandellDawson@users.noreply.github.com> * fix: made a few recommended changes of text * fix: moved </blockquote> to new line Co-Authored-By: RandellDawson <5313213+RandellDawson@users.noreply.github.com> * fix: removed extra space Co-Authored-By: RandellDawson <5313213+RandellDawson@users.noreply.github.com> * Update curriculum/challenges/english/05-apis-and-microservices/mongodb-and-mongoose/chain-search-query-helpers-to-narrow-search-results.english.md Co-Authored-By: RandellDawson <5313213+RandellDawson@users.noreply.github.com> * Update curriculum/challenges/english/05-apis-and-microservices/mongodb-and-mongoose/create-a-model.english.md Co-Authored-By: RandellDawson <5313213+RandellDawson@users.noreply.github.com> * fix: added the word The before code tag section
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Find people who like <code>burrito</code>. Sort them by name, limit the results to two documents, and hide their age. Chain <code>.find()</code>, <code>.sort()</code>, <code>.limit()</code>, <code>.select()</code>, and then <code>.exec()</code>. Pass the <code>done(err, data)</code> callback to <code>exec()</code>.
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</section>
## Tests
<section id='tests'>
```yml
tests:
- text: Chaining query helpers should succeed
testString: '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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```
</section>
## Challenge Seed
<section id='challengeSeed'>
</section>
## Solution
<section id='solution'>
```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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```
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</section>