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12 DevOps principles read today

DevOps means a concept to bring Development team and operation team together. So that you can speed up the deployment process. Before you start learning the tools you need to understand core principles.
The useful DevOps Principles to know for your project and interviewsTo deliver rapidly without affecting qualityCommunication and Collaboration are the key ideas in DevOps conceptMultiple deploys are possible- if code in Development team automatedOnce you commit the repository, it tests the code automatically against the automated test scriptsIf Build is successfully passed, it installs automatically in Testing environment When infrastructure is automated, it installs automatically to other serversMinor changes takes place in isolation, that means , it creates separate server to deploy minor changesSpeed in Devops, organizations to better serve their customers and compete more effectively in the market.Quality and Security teams are part of DevOpsAutomating the process, much better pro…

Top SAP HANA Iot must read Interview Questions (1 of 3)

The below are the list of awesome interview questions asked for SAP Hana interviews. Across the globe the below are the basic questions people are asking.
Q.1) What is in-memory computing?
A1) In-memory computing is a technology that allows the processing of massive quantities of data in main memory to provide immediate results from analysis and transaction. The data that is processed is ideally real-time data (that is, data that is available for processing or analysis immediately after it is created).

2) How in-memory computing works?A2) Keep data in main memory to speed up data access. Minimize data movement by using the columnar storage concept, compression, and performing calculations at the database level. Divide and conquer. Use the multi-core architecture of modern processors and multi-processor servers (or even scale out into a distributed landscape) to grow beyond what can be supplied by a single server.

3)What is the benefit of keeping data in memory?
A3) Data accessing from main memory is much faster than accessing data from Disk.

SAP hana interview questions
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4) If data is in memory(i.e RAM), what will happen in loss of Power?
A4) In database technology, atomicity, consistency, isolation, and durability (ACID) is the following set of requirements that ensures that database transactions are processed reliably:
  • A transaction must be atomic. If part of a transaction fails, the entire transaction must fail and leave the database state unchanged.
  • The consistency of a database must be preserved by the transactions that it performs.
  • Isolation ensures that no transaction interferes with another transaction.
  • Durability means that after a transaction is committed, it remains committed.
Although the first three requirements are not affected by the in-memory concept, durability is a requirement that cannot be met by storing data in main memory alone. Main memory is volatile storage. It loses its content when it is out of electrical power. To make data persistent, it must be on non-volatile storage, such as HDDs, solid-state drives (SSDs), or flash devices.

5) How SAP HANA will store data in non-volatile storage?
A5) The storage that is used by a database to store data (in this case, main memory) is divided into pages. When a transaction changes data, the corresponding pages are marked and written to non-volatile storage in regular intervals. In addition, a database log captures all changes that are made by transactions. Each committed transaction generates a log entry that is written to non-volatile storage, which ensures that all transactions are permanent.

6) How SAP HANA minimizes data movement?
A6) Although today's memory capacities allow keeping enormous amounts of data in-memory, compressing the data in-memory is still preferable. The goal is to compress data in a way that does not use up the performance that is gained while still minimizing data movement from RAM to the processor.

Related: SAP Hana Best Selected Interview Questions (Part 2 of 3)

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Hyperledger Fabric Real Interview Questions Read Today

I am practicing Hyperledger. This is one of the top listed blockchains. This architecture follows R3 Corda specifications. Sharing the interview questions with you that I have prepared for my interview.

Though Ethereum leads in the real-time applications. The latest Hyperledger version is now ready for production applications. It has now become stable for production applications.
The Hyperledger now backed by IBM. But, it is still an open source. These interview questions help you to read quickly. The below set of interview questions help you like a tutorial on Hyperledger fabric. Hyperledger Fabric Interview Questions1). What are Nodes?
In Hyperledger the communication entities are called Nodes.

2). What are the three different types of Nodes?
- Client Node
- Peer Node
- Order Node
The Client node initiates transactions. The peer node commits the transaction. The order node guarantees the delivery.

3). What is Channel?
A channel in Hyperledger is the subnet of the main blockchain. You c…