Sign In Start Free Trial
Account

Add to playlist

Create a Playlist

Modal Close icon
You need to login to use this feature.
  • Book Overview & Buying Apache Hive Essentials
  • Table Of Contents Toc
Apache Hive Essentials

Apache Hive Essentials

By : Dayong Du
4 (2)
close
close
Apache Hive Essentials

Apache Hive Essentials

4 (2)
By: Dayong Du

Overview of this book

If you are a data analyst, developer, or simply someone who wants to use Hive to explore and analyze data in Hadoop, this is the book for you. Whether you are new to big data or an expert, with this book, you will be able to master both the basic and the advanced features of Hive. Since Hive is an SQL-like language, some previous experience with the SQL language and databases is useful to have a better understanding of this book.
Table of Contents (12 chapters)
close
close

The SELECT statement


The most common use case of using Hive is to query the data in Hadoop. To achieve this, we need to write and execute the SELECT statement in Hive. The typical work done by the SELECT statement is to project the rows meeting query conditions specified in the WHERE clause after the target table and return the result set. The SELECT statement is quite often used with FROM, DISTINCT, WHERE, and LIMIT keywords. We will introduce them through examples as follows.

The SELECT * statement here means all the columns in the table are selected. By default, all rows are returned including duplicated rows. If the DISTINCT keyword is used, only unique rows from the table are selected and returned. The LIMIT keyword is used to limit the number of rows returned randomly. In addition, SELECT * scans the whole table/file without triggering MapReduce jobs, so it runs faster than SELECT <column_name>. Since Hive 0.10.0, the simple SELECT statements, such as SELECT <column_name&gt...

CONTINUE READING
83
Tech Concepts
36
Programming languages
73
Tech Tools
Icon Unlimited access to the largest independent learning library in tech of over 8,000 expert-authored tech books and videos.
Icon Innovative learning tools, including AI book assistants, code context explainers, and text-to-speech.
Icon 50+ new titles added per month and exclusive early access to books as they are being written.
Apache Hive Essentials
notes
bookmark Notes and Bookmarks search Search in title playlist Add to playlist download Download options font-size Font size

Change the font size

margin-width Margin width

Change margin width

day-mode Day/Sepia/Night Modes

Change background colour

Close icon Search
Country selected

Close icon Your notes and bookmarks

Confirmation

Modal Close icon
claim successful

Buy this book with your credits?

Modal Close icon
Are you sure you want to buy this book with one of your credits?
Close
YES, BUY

Submit Your Feedback

Modal Close icon
Modal Close icon
Modal Close icon