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  -           To check the current database list cmd> show dbs; -           To drop database cmd> db.dropdatabase( ); -           To create collection cmd> db.createCollection(“collection name”); or Use <collection name> -           To insert a document into the collection cmd> db.collectionname.insert([{}]); //insert many documents or one document           db.collectionname.insertOne({}); //inserts one document           db.collectionname.insertMany([{},{}]); //insert many documents -           To Print data in Json format cmd> db.collectionname.find( ).forEach(printjson); -        ...

1)    What is Document Database? Built around JSON-like documents, document databases are both natural and flexible for developers to work with. They promise higher developer productivity, and faster evolution with application needs. As a class of non-relational, sometimes called NoSQL database, the document data model has become the most popular alternative to tabular, relational databases.   2)    What makes document databases different from relational databases? 1. Intuitive Data Model: Faster and Easier for Developers Documents map to the objects in your code, so they are much more natural to work with. There is no need to decompose data across tables, run expensive JOINs, or integrate a separate ORM layer. Data that is accessed together is stored together, so you have less code to write and your users get higher performance. 2. Flexible Schema: Dynamically Adapt to Change A document’s schema is dynamic and self-describing, so you don’t need to f...

1)    What is NoSql? Ans: It is a non-relational database; some say the term “NoSQL” stands for “non-SQL” while others say it stands for “not only SQL.” Either way, most agree that NoSQL databases are databases that store data in a format other than relational tables. NoSQL databases are purpose built for specific data models and have flexible schemas for building modern applications. NoSQL databases are widely recognized for their ease of development, functionality, and performance at scale.   2)    How Does a NoSQL (nonrelational) Database Work? Ans: NoSQL databases use a variety of data models for accessing and managing data. These types of databases are optimized specifically for applications that require large data volume, low latency, and flexible data models, which are achieved by relaxing some of the data consistency restrictions of other databases.   Consider the example of modeling the schema for a simple book database:   In ...