7 Best Interview Questions and Answers about Teradata for 2022
Teradata is a popular system for managing databases. Many employers want to hire people who know how the system works and how to use it well. You can do better at your next database interview if you know what kinds of questions are often asked about Teradata. In this article, we list some questions you might be asked and give examples of how to answer them. Questions and Answers about Teradata for 2022
Common interview questions about Teradata and some sample answers
There are common Teradata questions that you might be asked at your interview, like:
- What is Teradata?
- What are the most important reasons to use Teradata?
- What kinds of tables does Teradata support?
- What are the new things about Teradata?
- Explain what a Node, a Parsing Engine, a Message Passing Layer, and an Access Module Processor are.
- In Teradata, what are BYTNET, Virtual Disk, and Virtual Storage?
- What would you do if the Fast Load scripts stopped working and all you had left were the Error Tables?
1. What is Teradata?
To use Teradata well, you need to know how it works. Show the interviewer that you know how to use Teradata well by telling them what it is, when to use it, and what its main features are. Try to show that you know how the system works in the real world.
Example: “Teradata is a relational database management system made by the Teradata Corporation. I have used it often to store a lot of data for a number of client projects.
Teradata is built on the idea of parallelism, which divides the work load into equal parts and runs tasks at the same time. It also works like a server and can be changed to handle different amounts of data. It works with the American National Standards Institute and is an open system that can run on one or more nodes. It has features that I can count on and that I use for many different kinds of projects.”
2. What are the most important reasons to use Teradata?
Teradata is better than other data management systems, so professionals could use it instead of them. Show the interviewer that you are sure you can use this software by listing four or five big benefits. You can include its ability to distribute load, its compatibility with ANSI, and its ability to grow in your answer.
Example: “I find Teradata to be a very effective framework because of its ability to spread out the load and its high performance, which comes from its large number of processors. Also, it is completely scalable, so I can change it for different projects. It works with ANSI, so I know that it is a standard service. It’s my favorite RDBMS for large, complex data storage projects because it can run multiple complex queries at the same time and can be used with different computer operating systems.
3.What kinds of tables does Teradata support?
A table type in Teradata is a specific way to store data, and it is important to understand the different types in order to use the Teradata system. Your answer should show that you know what the four types of tables are. You can name each kind and say a few words about it.
Example answer: “The four types of tables that can be used are the Permanent Table, the Derived Table, the Volatile Table, and the Global Temporary Table.” Each kind is used for something very different. For example, the Permanent Table is the type that is used by default to store data that doesn’t change. It’s used when queries are being run. Most of the intermediate data results are in the Derived Table.
The Volatile Table is used to store data while sharing data, sending data, or doing complex calculations. It keeps intermediate data and deletes it when the user session is over. The Global Temporary Table stores values of data that are used in applications. This data is deleted at the end of each session.
4. What are the new things about Teradata?
A good candidate for a job that requires using Teradata should know how to use it in the most recent way. List the new features of Teradata to show that you have the right skills for the job. You can talk about how the new features have changed your life.
Example: “The Teradata Viewpoint is a new feature that helps me save time and money by letting me manage several Teradata products with a single operational view. Another new feature is automated temporal analytics, which makes it easier to track changes in historical data and look at how data changes over time. Another great new feature is the ability to compress data better, which lowers the cost of storing data and makes the system run better.
5. Explain what a node, a parsing engine, a message passing layer, and an access module processor are.
A good understanding of Teradata architecture can make the difference between a good candidate and a good one. If you can show the interviewer that you understand these things, you will stand out. You can answer this question by saying what each part of the system does.
“A Teradata system is made up of four main parts: the Node, the Parsing Engine, the Message Passing Layer, and the Access Module Processor.” A Node is one server in the system. It is the most basic unit of the system. Each Node has an operating system, memory, disk space, a CPU, and a Teradata RDBMS.
The Parsing Engine gets messages from clients and makes plans for how to carry out those messages. It checks each request for syntax errors, checks the user’s access, checks to see if the object of the SQL query is available, sets up the plan to be run, sets up the SQL query, and sends the result.
The Parsing Engine, the Nodes, and the Access Module all talk to each other through the Message Passing Layer. The Networking Layer is the name of this part of the system. The Access Module Processor helps the physical data be read, written, and stored.
6.In Teradata, what are BYTNET, Virtual Disk, and Virtual Storage?
A Teradata developer uses the BYTNET, Virtual Disk, and Virtual Storage a lot and needs to know what each one can do. Your answer should show the interviewer that you know how these major Teradata components work.
“The BYTNET is Teradata’s network, and it lets the Nodes talk to each other. It is how Parsing Engines and Access Module Processors talk to each other. It has more than one way to connect, and it changes its settings to get rid of paths that don’t work. Most of the time, the Teradata MPP system has two BYTNETs.
Each Access Module Processor is linked to one Virtual Disk. A Virtual Disk is a group of physical disks that are set up like an Array.
Virtual Storage is a hybrid system that stores and manages data in an intelligent way. For example, it finds hot data, decompresses cold data when its use goes up, and moves it to other storage systems with faster speeds.
7.What would you do if the Fast Load scripts stopped working and all you had left were the Error Tables?
When using Teradata, it is important to know how to deal with system-based problems. Your answer should show that you understand how to fix problems with this system. Describe how you would think and act in this situation to show how you would handle it.
Example: “If all I have are the Error Tables, I know I can’t restart the project without changing the code. If I am working on a small project, I would just run the project again. But if I was working with a lot of data, like when I was trying to load millions of rows, I would try to start the project over again.
In this case, running the old file is one way to start over. I wouldn’t just get rid of the Error Tables. Then I’d check the script and file for mistakes, fix the mistakes, and run.
Using the statements end loading and beginning to run the script and a new file is another way to start over. This could unlock the table I need and get rid of the record in the table where fast-logs are kept. If that works, I can run the whole script again and start the project over from the beginning.”
