1. Which internal algorithm used for NameNode to decide where the replica of a block will be stored exactly?
2. What will happen if a block of data is corrupted?
3. In the SCALA Program how to find out the number of transformations and actions?
4. If we are executing a query, how we can know that which are the joins taking more time especially in Hive and Spark query?
5. Scenario – I: In Hive, we have two tables A and B. B is the master table and A is the table which receives the updates of certain information. So I want to update the table B using the latest updated columns based upon the id
Question: How do we achieve that and what is exact query we use?
6.If Spark jobs are all failed without checking log files without WebUI how to handle it?
7. How to provide Security in Ambari without Kerberos?
8. Can you explain about High Availability Cluster in Hadoop Environment?
9. If you have a Spark job and there are 25 node cluster. How many executors are will be created by default?
10. How to change the column names in HIVE while importing the data into hive using Apache SQOOP?
11. How to handle the data type mismatch while importing the data from RDBMS to HIVE table?
12. How to handle when NULLS are present in the partition column? What is the internal mechanism for this simple scenario?
For suppose we have 4 node cluster having 128 GB ram per node, then we have 532 GB memory, now we have to process 1000 GB of data.
Question ) How spark process this data is more than available memory?
14. Did you use email reader in Oozie? How do you configure it?
15. In a Scala programming, you have to make two restful API calls, let’s say we have API 1 and API 2 and we have API 3. Then you have concurrently call API 1and API 2 and have to wait to finish both the call and make the 3rd call. How do you thin SCALA concurrently?