Last Sync: 2022-08-11 13:00:04

Databases/MongoDB/Querying_a_collection_with_Mongoose.md

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+---
+tags:
+- Databases
+- mongo_db
+- node-js
+- mongoose
+---
+
+# Query a Mongo collection with Mongoose 
+
+We now have the following entries in our `courses` collection:
+
+```js
+{
+  name: 'Python Course',
+  author: 'Terry Ogleton',
+  tags: [ 'python', 'backend' ],
+  isPublished: true,
+  _id: new ObjectId("62f4e2527ac4aa2c30d41d23"),
+  date: 2022-08-11T11:04:50.750Z,
+  __v: 0
+}
+{
+  name: 'Javascript Course',
+  author: 'Tosh Gnomay',
+  tags: [ 'js', 'frontend' ],
+  isPublished: true,
+  _id: new ObjectId("62f4e2527ac4aa2c30d41d24"),
+  date: 2022-08-11T11:04:50.750Z,
+  __v: 0
+}
+
+```
+
+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:
+
+* `find`
+* `findById`
+* `findByIdAndRemove`
+* `findByIdAndUpdate`
+* `findOne`
+* `findOneAndUpdate`
+* `findOneAndRemove`
+* ...
+
+The various `find` methods return a value that is promisified.
+
+## Return all values in a collection: `find`
+
+```js
+async function getCourses(){
+  const courses = await Course.find()
+  console.log(courses)
+}
+```
+
+### Filter values returned
+
+```js
+async function getCourses(){
+  const courses = await Course.find({author: 'Tosh Gnomay', isPublished: true})
+  console.log(courses)
+}
+```