Create INDEX in Mongodb

Index are created on the fields to get better performance while data retrieval , index can be created in two ways,

• Ascending order (1)
• Descending order (-1)

Syntax:  db.collection.createIndex(‘field’:’option’)

Example:

Creating the index for ‘studentDetails’ collection for ‘Name’ field in ascending order          

db.studentDetails.createIndex({Name:1})

Creating the index for ‘studentDetails’ collection for ‘Department’ field in descending order 

db.studentDetails.createIndex({Department:-1})