Database Interview Questions
- 0of 0 votes
AnswersDesign database schema with entity and relations to store the family tree of a person.
- neer.1304 June 01, 2020 in United States| Report Duplicate | Flag | PURGE
Microsoft Senior Software Development Engineer Database - 0of 0 votes
AnswerDesign DB schema for maintaining e-commerce various category ,sub category ,sub-sub category and so on.
- neer.1304 July 12, 2019 in United States| Report Duplicate | Flag | PURGE
Boomerang Commerce Database - 0of 0 votes
AnswerWe have a database that allows 2 concurrent writes and 3 concurrent reads. Each read/write operation takes 10ms to complete. What is the time taken to process all the requests in the orders mentioned (all requests can be assumed to be coming in at the same instant of time and are operating on a single row in a table) - 1. write, write, read, write, read, read, write, read 2. read, write, read, write, read: *
- __Joker October 10, 2018 in India
1. 30 ms 2. 10ms
1. 60 ms 2. 10ms
1. 10 ms 2. 10ms
1. 20 ms 2. 10ms
1. 10ms 2. 20ms
1. 60ms 2. 30ms| Report Duplicate | Flag | PURGE
unknown Software Developer Database - -1of 3 votes
AnswersFor Amazon SDE-1 On Campus Interview, what are the topics I should study in Database Management ?
- akisonlyforu June 08, 2018 in India
Just don't name the topics. Please elaborate too.| Report Duplicate | Flag | PURGE
Amazon SDE1 Database - 0of 0 votes
AnswersTable: Customers
- prasad.hybris May 02, 2018 in United States
id | name
1|alice
2|bob
3|carol
Table: Orders
id | customer_id | content
1|1|House
2|2|car
3|2|dog
4|10|cow
please write a query which returns all of the invalid orders (where invalid means their customer_id does not have an associated customer)
4|10|cow| Report Duplicate | Flag | PURGE
Google Technical Support Engineer Database - -2of 2 votes
AnswersUsing Google BigQuery documentation, provide at least three (3) possible failure modes that could cause following customer problem:
- prasad.hybris April 03, 2018 in United States
""" I am ingesting data regularly in streaming mode into my mobile-events table, querying the data back however shows timestamps six hours behind. Please help. """
You can use public BigQuery documentation for the client side and make assumptions about the serving side based on your experience with other similar products, provided the serving stack spreads across multiple machines and microservices.| Report Duplicate | Flag | PURGE
Google Cloud Support Associate Database - -1of 1 vote
AnswersBIG DAT AND MACHINE LEARNING
- prasad.hybris April 03, 2018 in United States
Hi Cloud Support,
I have records like this in BigQuery:
logs.datetime: ''2017-07-01T13:51:03"
logs.type: "worker"
logs.message: "Starting pipeline"
apps.name: "reader_af45c9"
apps.log_type: "worker"
And I'm trying to run this query:
select logs.datetime, logs.type, logs.message, apps.name
from logs inner join apps on logs.type = apps.log_type
where logs.datetime > "2017-07-01T00:00:00" and logs.datetime < "2017-07-02T00:00:00"
group by apps.name;
But it's not working. Can you help me?| Report Duplicate | Flag | PURGE
Google Cloud Support Associate Database - 0of 0 votes
AnswersMS FTE Question:
- mktauseef October 04, 2017 in United States
Find the gap from 1,2,5,6,10
Answer : 3,4,7,8,9| Report Duplicate | Flag | PURGE
Data Engineer Database - 4of 4 votes
AnswersGroup by with having related questions. ER provided was customer table.
- harshvp April 12, 2017 in United States for Search| Report Duplicate | Flag | PURGE
Facebook Data Engineer Database - 0of 0 votes
AnswersFind the % of all male customers in a specific area out of all the customers in that area.
- harshvp April 12, 2017 in United States for Search| Report Duplicate | Flag | PURGE
Facebook Data Engineer Database - 0of 0 votes
AnswersGet total number of all the departments of each employees
- harshvp April 12, 2017 in United States for Search| Report Duplicate | Flag | PURGE
Facebook Data Engineer Database - 0of 0 votes
AnswersHow DataBase replication Happens in MySql Server.
- DuttaJ March 23, 2017 in India
how to create a slave DB from an already running master Server.| Report Duplicate | Flag | PURGE
Concur Technical Architect Database - 0of 0 votes
AnswersDesign Amazon Recommendations Feature. Focus on designing how would you store and make it accessible fast? What would be class design like for the class which would provide list of products which people bought similar to a given product? How would you test that class?
- Anonymous February 07, 2017| Report Duplicate | Flag | PURGE
Amazon SDE-2 Data Structures Database Object Oriented Design - 0of 2 votes
Answerswrite a SQL query to retrieve the number of students that received a GPA of 3 or 4. the query should return Total number of students that receive a GPA of 3 separate from Total number of students that receive GPA 4.
- aryan October 19, 2016 in United States
Schema:-
Student:- Student_ID, name, phoneno, email, gpa, gradyear
Classes: Class_ID, name, description
student_classes:- Class_ID, Student_ID, Grade| Report Duplicate | Flag | PURGE
Amazon Software Engineer Database - 0of 0 votes
AnswersWe all know databases are very very slow. In fact they are so slow that very serious people who wants to do volumes of read operation and search operations write their own implementation. In this question, you would be asked to do the same, for a very limited operation - select.
Every item stored has this field called timestamp.
Now, here is the problem you need to solve :select items where time < some_time select items where time < some_time and time < another_time select items where time > some_time
Imagine you have millions of data rows. How to store it in HDD, and how to load, entirely your problem. None is going to insert anything on existing data - only read.
- NoOne October 14, 2016 in India
Write an algorithm that solves this problem, and a data structure that works as storage for the data.| Report Duplicate | Flag | PURGE
SDET Algorithm Database - -2of 2 votes
AnswersDesign unix file system in database.
- mohit.kum85 August 16, 2016 in United States| Report Duplicate | Flag | PURGE
Amazon Software Developer Database - 0of 0 votes
AnswersBuild an in-memory DB that supports many commands and transactions.
- adch123 May 25, 2016 in United States
Similar to redis database (Redis.io)| Report Duplicate | Flag | PURGE
Database Java Object Oriented Design Software Design - 0of 0 votes
AnswersDatabase table:
- asdf April 13, 2016 in United States
Name Age Salary Dept
Alice 22 100 IT
Bob 33 150 IT
Charlie 44 180 Operations
Dale 50 200 Finance
What are the apparent problems that you can identify in the database table?| Report Duplicate | Flag | PURGE
Morgan Stanley Associate Database - 0of 0 votes
AnswersWhat technology is used by Autoportal.com to store there huge Databse?
- bellaedwardwriter August 25, 2015 in India| Report Duplicate | Flag | PURGE
Autoportal.com Analyst Database - 0of 0 votes
AnswersNot sure what topic this falls under.
- moriarty.rj June 30, 2015 in United States
"Improve metrics on the system."
Intentionally vague requirement to see how I ask questions. In my case, it ended up being a discussion about making database queries faster.| Report Duplicate | Flag | PURGE
Amazon Software Developer Database Ideas Problem Solving System Design - 0of 0 votes
AnswersIf given a binary file, with data like lat, long, weather, temp in key:value. It's a structured data how would u ingest it. what are the steps that are being taken before Hive process starts.
- Tom Walker June 07, 2015 in United States
- serde (serializartion deserialization). parque etc.| Report Duplicate | Flag | PURGE
Amazon Software Developer Algorithm Data Mining Data Structures Database Distributed Computing Java SQL - 0of 0 votes
AnswersLets say if Mongo captures user views and oracle captures purchases. How would you design realtime system that answers question "give me avg. no. of views of users by purchases".
- Tom Walker June 07, 2015 in United States
So if a user watch a trailer 10 times and then decides to buy a video. How would you calculate it. He was looking for QUEUE.
He could have gone on more details but stopped because i didn't give details on this.| Report Duplicate | Flag | PURGE
Amazon Software Developer Data Mining Data Structures Database - 1of 1 vote
AnswersHow would you increase efficiency of a hive query?
- Tom Walker June 07, 2015 in United States| Report Duplicate | Flag | PURGE
Amazon Software Developer Data Mining Data Structures Database Debugging SQL - 0of 0 votes
AnswerWhat is distribute cache in Hadoop?
- Tom Walker June 07, 2015 in United States| Report Duplicate | Flag | PURGE
Amazon Software Developer Data Structures Database - 0of 0 votes
AnswerWhat do you mean by combiner?
- Tom Walker June 07, 2015 in United States| Report Duplicate | Flag | PURGE
Amazon Software Developer Data Mining Data Structures Database Distributed Computing - 0of 0 votes
AnswersAfter map phase partition, shifting, sorting happen. What does it mean?
- Tom Walker June 07, 2015 in United States| Report Duplicate | Flag | PURGE
Amazon Software Developer Data Mining Data Structures Database Java - 0of 0 votes
AnswerWhat is input split in hadoop.
- Tom Walker June 07, 2015 in United States| Report Duplicate | Flag | PURGE
Amazon Software Developer Data Mining Data Structures Database Java SQL - 0of 0 votes
AnswersAs I interviewing for Big data position. Asked Hadoop question :-
- Tom Walker June 07, 2015 in United States
Difference between TextInput vs Key Value format in Hadoop.| Report Duplicate | Flag | PURGE
Amazon Software Developer Data Mining Data Structures Database Java design - 0of 0 votes
AnswersDesign Bing search.
- Tom Walker June 07, 2015 in United States| Report Duplicate | Flag | PURGE
Microsoft Software Developer Algorithm Coding Database Java Object Oriented Design Software Design - 0of 0 votes
AnswersHow Solr/Lucene or Elasticsearch work? For what purpose are they used?
- Tom Walker June 07, 2015 in United States| Report Duplicate | Flag | PURGE
Microsoft Software Developer Data Mining Data Structures Database Large Scale Computing SQL