Added mongoose cheatsheet

src/pages/sheet/mongoose.md

@@ -0,0 +1,118 @@
+# MongoDB and Mongoose Cheatsheet
+
+## Mongoose Installation
+
+* `$ sudo npm install mongoose`: install the latest Mongoose locally`
+* `$ sudo npm install [email protected] --save`: install Mongoose v3.8.20 locally and save to `package.json`
+
+## Mongoose Basic Usage
+
+```
+var mongoose = require('mongoose')
+var dbUri = 'mongodb://localhost:27017/api'
+var dbConnection = mongoose.createConnection(dbUri)
+var Schema = mongoose.Schema
+var postSchema = new Schema ({
+  title: String,
+  text: String
+})
+var Post = dbConnection.model('Post', postSchema, 'posts')
+Post.find({},function(error, posts){
+  console.log(posts)
+  process.exit(1)
+})
+```
+
+## Mongoose Schema
+
+* `String`
+* `Boolean`
+* `Number`
+* `Date`
+* Array
+* `Buffer`
+* `Schema.Types.Mixed`
+* `Schema.Types.ObjectId`
+
+## Create, Read, Update, Delete (CRUD) Mongoose Example
+
+```
+// Create
+var post = new Post({title: 'a', text: 'b')
+post.save(function(error, document){
+  ...
+})
+
+
+// Read
+Post.findOne(criteria, function(error, post) {
+  ...
+})
+
+// Update
+Post.findOne(criteria, function(error, post) {
+  post.set()
+  post.save(function(error, document){
+    ...
+  })
+})
+
+// Delete
+Post.findOne(criteria, function(error, post) {
+  post.remove(function(error){
+    ...
+  })
+})
+```
+
+## Mongoose Model Methods
+
+
+* `find(criteria, [fields], [options], [callback])`: find document; callback has error and documents arguments
+* `count(criteria, [callback]))`: return a count; callback has error and count arguments
+* `findById(id, [fields], [options], [callback])`: return a single document by ID; callback has error and document arguments
+* `findByIdAndUpdate(id, [update], [options], [callback])`: executes MongoDB's findAndModify to update by ID
+* `findByIdAndRemove(id, [options], [callback])`: executes MongoDB's findAndModify to remove
+* `findOne(criteria, [fields], [options], [callback])`: return a single document; callback has error and document arguments
+* `findOneAndUpdate([criteria], [update], [options], [callback])`: executes MongoDB's findAndModify to update
+* `findOneAndRemove(id, [update], [options], [callback])`: executes MongoDB's findAndModify to remove
+* `update(criteria, update, [options], [callback])`: update documents; callback has error, and count arguments
+* `create(doc(s), [callback])`: create document object and save it to database; callback has error and doc(s) arguments
+* `remove(criteria, [callback])`: remove documents; callback has error argument
+
+## Mongoose Document Methods
+
+* `save([callback])`: save the document; callback has error, doc and count arguments
+* `set(path, val, [type], [options])`: set value on the doc's property
+* `get(path, [type])`: get the value
+* `isModified([path])`: check if the property has been modified
+* `populate([path], [callback])`: populate reference
+* `toJSON(options)`: get JSON from document
+* `validate(callback)`: validate the document
+
+## Query Helpers
+```
+animalSchema.query.byName = function(name) {
+    return this.where({ name: new RegExp(name, 'i') });
+  };
+
+  var Animal = mongoose.model('Animal', animalSchema);
+
+  Animal.find().byName('fido').exec(function(err, animals) {
+    console.log(animals);
+  });
+
+  Animal.findOne().byName('fido').exec(function(err, animal) {
+    console.log(animal);
+  });
+ ``` 
+  ## Indexes
+ ```
+  var animalSchema = new Schema({
+    name: String,
+    type: String,
+    tags: { type: [String], index: true } // field level
+  });
+
+  animalSchema.index({ name: 1, type: -1 }); // schema level
+```