Sharing recent Interview questions on Hadoop.

[Raj]

JAVA

How comfortable on 1 - 10 scale.
What is Collection Interface, difference b/w SET & MAP.
What are Object Oriented Programming (OOPS) concepts, and explain.
What is the difference b/w Interface & Abstract class, when you need to define them?

Hadoop:

What is your work? how you get work & and with whom you worked?
What are the different configuration settings needs to be done to setup HDFS and different configuration files you use?
Explain the JobConf?
What happens to the data if any job fails in b/w?
What is the difference b/w Comparable & Comparator Classes.
How do you run or execute a Job? how does it executes.
What is the difference b/w External Table & Internal Table in HIVE.
How Partitions can be done on HIVE Tables(partition the file using a Date field), and what Schema you used.
What is difficult query you have written using HiveQL?
How can you improve performance of a MapReduce Job without increasing number of Reducers because if you increase it will also effect other Jobs/users.
Have heard about UDF's and how comfortable using UDF(User defined functionality).