64 lines
2.0 KiB
Markdown
64 lines
2.0 KiB
Markdown
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---
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title: Chain Search Query Helpers to Narrow Search Results
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---
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## Chain Search Query Helpers to Narrow Search Results
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1. To create but not execut a find query
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```javascript
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Model.find( {name: 'Leah'} )
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```
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2. To store the find query into a variable for later use:
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```javascript
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var findQuery = YourModel.find( {name: 'Leah'} )
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```
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3. To sort an array:<br>
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```javascript
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yourArray.sort( {age: 1} ) // Here: 1 for ascending order and -1 for descending order.
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```
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4. To limit an array's size:
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```javascript
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yourArray.limit(5) // return array which has 5 items in it.
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```
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5. To hide certain property from the result:
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```javascript
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yourArray.select( {name: 0, age: 1} ) // Here: 0 means false and thus hide name property; 1 means true so age property will show.
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```
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6. To exec this query, you can either:</br>
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1) Callback:
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```javascript
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YourQuery.exec(function(err, docs) {
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//do something here
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})
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```
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Or 2) Promise
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```javascript
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YourQuery.exec.then(function(err, docs) {
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//do something here
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})
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```
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7. Chain it all together:
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```javascript
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Person.find({age: 55}).sort({name: -1}).limit(5).select( {favoriteFoods: 0} ).exec(function(error, people) {
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//do something here
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})
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```
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</br>
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</br>
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This is a stub. <a href='https://github.com/freecodecamp/guides/tree/master/src/pages/certifications/apis-and-microservices/mongodb-and-mongoose/chain-search-query-helpers-to-narrow-search-results/index.md' target='_blank' rel='nofollow'>Help our community expand it</a>.
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<a href='https://github.com/freecodecamp/guides/blob/master/README.md' target='_blank' rel='nofollow'>This quick style guide will help ensure your pull request gets accepted</a>.
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