1. Write Operations

2. Agenda
Create Collection
Insert
Update
Remove

3. Create Collection db.createCollection(“COLLECTION_NAME”)
You can also insert into a collection that doesn’t exist yet. This will create a new collection
db.people.insertOne( { user_id: "abc123", age: 55, status: "A" } )

4. Insert MongoDB db.collection.insert()
Inserts a new doc with the age, name, status, and _id fields

5. Insert Mysql

6. Insert
Adding a doc without an _id field is ok. MongoDB will auto generate a unique id.
If you specify the _id field, it must be unique to the current collection.

7. Insert One
db.collection.insertOne() inserts a single document into a collection
db.inventory.insertOne(
{ item: "canvas", qty: 100, tags: ["cotton"], size: { h: 28, w: 35.5, uom: "cm" } } )
Query the database to find the document that you just inserted:
db.inventory.find( { item: "canvas" } )

8. Insert Multiple db.collection.insertMany() inserts multiple documents.
Pass an array of docs to insertMany
db.inventory.insertMany([
{ item: "journal", qty: 25, tags: ["blank", "red"], size: { h: 14, w: 21, uom: "cm" } },
{ item: "mat", qty: 85, tags: ["gray"], size: { h: 27.9, w: 35.5, uom: "cm" } },
{ item: "mousepad", qty: 25, tags: ["gel", "blue"], size: { h: 19, w: , uom: "cm" } } ])

9. Update MongoDB Updates a document that matches the criteria
Updates are atomic within a single document

10. Update Mysql

11. Update One
db.inventory.updateOne( { item: "paper" }, { $set: { "size.uom": "cm", status: "P" } } )

12. Update Many
db.books.updateMany( { stock: { $lte: 10 } }, { $set: { reorder: true } }, { multi: true } )

13. Upsert An update that, if the doc exists, it will do an update
If the doc does not exist, it will do an insert
db.people.update(
{ name: "Andy" }, {
name: "Andy",
rating: 1,
score: 1 },
{ upsert: true } )

14. Update Operators Lots of different update operators
Only concerned with $set
db.products.update(
{ _id: 100 },
{ $set: { "details.make": "zzz" } } )

15. Remove MongoDB Deletes doc from collection
Accepts a query criteria to determine which docs to remove

16. Remove Mysql