65 lines
1.3 KiB
Markdown
65 lines
1.3 KiB
Markdown
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---
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tags:
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- Databases
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- mongo_db
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- node-js
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- mongoose
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---
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# Query a Mongo collection with Mongoose
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We now have the following entries in our `courses` collection:
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```js
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{
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name: 'Python Course',
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author: 'Terry Ogleton',
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tags: [ 'python', 'backend' ],
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isPublished: true,
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_id: new ObjectId("62f4e2527ac4aa2c30d41d23"),
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date: 2022-08-11T11:04:50.750Z,
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__v: 0
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}
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{
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name: 'Javascript Course',
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author: 'Tosh Gnomay',
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tags: [ 'js', 'frontend' ],
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isPublished: true,
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_id: new ObjectId("62f4e2527ac4aa2c30d41d24"),
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date: 2022-08-11T11:04:50.750Z,
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__v: 0
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}
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```
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Now we will query the collection. This capability is provided via the Mongoose schema class we used to create the `Course` [model](/Databases/MongoDB/Create_collections_and_documents_with_Mongoose.md#models). We have the following methods available to use from the schema:
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* `find`
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* `findById`
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* `findByIdAndRemove`
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* `findByIdAndUpdate`
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* `findOne`
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* `findOneAndUpdate`
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* `findOneAndRemove`
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* ...
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The various `find` methods return a value that is promisified.
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## Return all values in a collection: `find`
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```js
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async function getCourses(){
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const courses = await Course.find()
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console.log(courses)
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}
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```
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### Filter values returned
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```js
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async function getCourses(){
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const courses = await Course.find({author: 'Tosh Gnomay', isPublished: true})
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console.log(courses)
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}
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```
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