Advance Hbase Interview Questions

Hadoop Interview Questions and Answers | Big Data Interview Questions | Edureka This Edureka video on Hadoop Tutorial on Hadoop Interview Questions and Answers will help you to prepare yourself for Big Data and Hadoop interviews.

  • Apache HBase is a NoSQL column oriented database which is used to store the sparse data sets. It runs on top of the Hadoop distributed file system (HDFS) and it can store any kind of data.
  • Clients can access HBase data through either a native Java API, or through a Thrift or REST gateway, making it accessible from any language.
  • ♣ Tip: Before going through this Apache HBase interview questions, I would suggest you to go through Apache HBase Tutorial and HBase Architecture to revise your HBase concepts.

    HBase Logo - EdurekaNow moving on, let us look at the Apache HBase interview questions.

    What do you mean by WAL?

    It stands for Write Ahead Log. It is basically a log that is responsible for recording all the changes in the data irrespective of the mode of their change. Generally, it is considered the standard sequence file. It is actually very useful to consider after the issues like a server crash or failure. The users can still access data through it during such problems.

    2 Tell a few important features of the Apache Hbase?

    The following are the features of the Apache Hbase

  • Hbase is capable to be used while performing a lot of tasks that need modular or linear scaling
  • All the tables are distributed on the cluster through regions.
  • With respect to the growth in the data, the regions automatically grow and split
  • There are several bloom filters that Hbase support
  • The use of Block Cache in the Hbase is totally allowed
  • Hbase is capable to handle volume query optimization when the data needs are complex
  • What constitutes a cell in HBase?

    Cells are the smallest units of HBase tables, holding the data in the form of tuples. A tuple is a data structure having multiple parts. In HBase, it consists of {row, column, version}.

    1 Discuss deletion and tombstone markers in HBase.

    In HBase, a normal deletion process results in a tombstone marker. The deleted cells become invisible, but the data represented by them is actually removed during compaction. HBase has three types of tombstone markers:

  • Version delete marker: It marks a single version of a column for deletion
  • Column delete marker: It marks all versions of a column
  • Family delete marker: It sets up all columns of a column family for deletion
  • Here, it needs to be noted that a row in HBase would be entirely deleted after major compaction. Therefore, when you delete and add more data, the Gets may be masked by tombstone markers, and you may not see the inserted values until after the compactions.

    upGrad’s Exclusive Data Science Webinar for you –

    Watch our Webinar on How to Build Digital & Data Mindset?

    Compare Hbase and Hive and tell the noticeable differences?

    Both are based on Hadoop but both are different from one another. Hive is generally considered as one of the best available data warehouse infrastructure. The operations of Hbase are limited when compared to the Hive. However, when it comes to handling real-time operations, the Hbase is good. On the other hand, the Hive is preferred only when the querying of data is the prime need.

    Related Article: Hive vs HBase

    Hbase Interview questions and answers|NoSQL database|Big data|data engineer|hadoop developer|Hbase

    Related Posts

    Leave a Reply

    Your email address will not be published. Required fields are marked *