Apache Hive Interview Questions and Answers

Ques 16. How can you join tables in Hive?

You can perform joins in Hive using the standard SQL syntax, such as INNER JOIN, LEFT JOIN, and RIGHT JOIN.

Example:

SELECT * FROM table1 t1 INNER JOIN table2 t2 ON t1.id = t2.id;

Ques 17. What is the purpose of Hive HCatalog?

HCatalog is a storage and table management layer for Hadoop that enables sharing of data between Pig, MapReduce, and Hive.

Ques 18. How can you handle null values in Hive?

You can use the 'COALESCE' function or 'CASE' statement to handle null values in Hive queries.

Example:

SELECT column1, COALESCE(column2, 'NA') FROM table_name;

Ques 19. What is the purpose of Hive indexes?

Hive indexes provide a way to speed up query processing by allowing faster access to rows that meet certain conditions.

Ques 20. Explain dynamic partitioning in Hive.

Dynamic partitioning in Hive allows the automatic creation of partitions based on a specified column during the data insertion process.