SQL

 DDL -> Data Definition Language

Create, Drop , Alter, Truncate, Comments

DQL -> Data Query Language

Select, From, Where, Group by

DML-> Data Manipulation Language

Insert , Update, Delete

DCL -> Data Control Language

Grant, Revoke

TCL-> Transaction Control Language

Begin Tran, Commit , Rollback , Save point

Microservices Questions and Answer

 How the .NET core kestrel web server Works?

 Libuv manager I/O

Sagar Pattern

Breaks a transaction into a sequence of smaller local  transaction . If a step fails , They system executes compensating transactions to undo preceding changes(Approval or Rejected flow)

CQRS

Command Query Responsibility segregation

Command - one Microservices

Query - One Microservices 

Idempotency

• When same button pressed multiple time
• API header Need to add with Idempotency-key 
• IMemoryCache - will hold the key and handle id(Redis cache)

ConCurrency

     If a same resources in the requested multiple time

     Lock - Feature

Rate Limiter

• No. of request a client can make to your API in a time frame
• Middleware need to configure

Strategy Pattern:

Used for below codings

• Payment
• Routing
• Data Compression

Syn program in Microservices

• HTTP Rest
• GRPC

React js Question and answers

 

What are React JS data transfer techniques	1.Prop drilling        a. Parent to child        b. Child to Parent(usecallback) 2. Global state sharing – Context API 3. state management lib redux 4. React Route URL (useParams)
Reactjs components lifecycle	1.Mounting       a. constructor       b.getderivedstatefromprop       c.render       d.componentsdidmount 2.Updating      a.getderivedstatefromprop      b.shouldcomponentupdate       c.render       d.getsnapshotbeforeupdate       e.componentsdidupdate   3.Unmounting      a.componentWillUnmount
How to post data using React js	Fetch Axios
How to post data using Node js	Express js Axios
i have to post 100 different request and get response at same time in react js	Promise All   Promise.allSettled