MongoDB CRUD Operations

 CRUD Operations 

•CRUD == Create, Read, Update, Delete

 •Create Operations – 

   •Create and Add new documents to the collections

 •Read Operations –

    •Retrieve data from the collections 

•Update Operations – 

•Modify existing documents in the collection 

•Delete Operations – 

•Delete or remove documents from the collections

Database and Collection Creation

•List databases

 •List collections 

•Create new database “myNewDB” 

•Create new collections “myNewCollections2” and “myNewCollections3” 

•Switch between the databases 

•Capped Collections 

•Create Capped Collection 

•Create capped collection with size 100000 bytes 

•Specify maximum number of documents 

•Check if collection is capped 

Create (Insert) Operation 

•Add new documents to the collection

•It creates the collection 

•Targets single collection 

•Automic write operations on the single document level 

•Unique _id field, which acts as primary key 

•Auto-creates _id field if not present 

Read (Query) Operation

•Query a collection for documents 

•You can specify query filters 

•You can specify the list of fields to

•Can use indexes

•Can perform sort and limit operations

 Update Operation

•Modifies existing documents in a collection

 •Targets a single collection 

•Atomic write operations on the single document level 

•You can specify criteria, or filters 

•You cannot update the value of the _id field

Delete (Remove) Operation

•Removes documents from a collection 

•Targets a single collection 

•Atomic write operations on the single document level 

•You can specify criteria, or filters 

•Delete operations do not drop indexes