Database

*JWT *

JWT access token means a compact and self-contained way for securely transmitting information between parties as a JSON object. JWT normally uses a secret key to secure from others.
We use this for authorization and information exchange. Most common for using this JWT for authorization. When a user logged in, each subsequent request will include the JWT and allow the user to access routes, services and resources that are permitted with that token.
Other information exchange means when JSON web tokens are a good way of securely transmitting information between parties.
JSON web tokens consist of three parts separated by dots( . ),which are mainly: Header, Payload and Signature.

*CRUD Operations *

When we worked with a database we must know about CRUD Operations. We need to know four basic functions of persistent storage. They are: create, read, update and delete. It is the foundation of most dynamic websites. We need to differentiate CRUD from the HTTP action verbs.
When you want to create a new record on your database you should use the ‘POST’ method. If you need something to update your database you need to use the ‘PUT or PATCH’ method and sometimes you need to delete something from your database you need to use the method ‘DELETE’. Using these CRUD Operations users can edit, update, delete or browse the record database.
CRUD operations are very useful for a programmer. A programmer handles this very easily. CRUD operations performance is very useful for us. The SQL server will create a new execution plan for the query. You can remove, add something using these CRUD operations.

*What is Nodejs? Difference between Nodejs and javaScript *

Nodejs is a popular tool for any project with an open-source, cross-platform JavaScript runtime environment. Nodejs library runs web applications outside the client’s browser. Nodejs used to create server-side web applications.
Difference between Nodejs and javaScript are :
Nodejs : Nodejs is a Javascript runtime environment. Mostly used on the server-side. Written in C,C++ and Javascript. Express js is a nodeJs module.
JavaScript : A programming language that is used for writing scripts on the website. Used on the client-side. Written in C++. Frameworks are RamdaJs, TypeJs.

*Relational database (MySql) *

MySql Relational Database is a collection of data items with pre-defined relationships between them. It is an assemblage of relational data that is structured or organized in the form of tables, columns and rows and tables represent the objects, columns represent the fields and rows represent the records. SQL is a programming language which is used to create, update, delete and manage the tables and its contents, as MYSQL is supported with the basic SQL queries.