Book Image

Apache Hive Essentials

By : Dayong Du
Book Image

Apache Hive Essentials

By: Dayong Du

Overview of this book

Table of Contents (17 chapters)
Apache Hive Essentials
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Data exchange – INSERT


To extract the data from Hive tables/ partitions, we can use the INSERT keyword. Like RDBMS, Hive supports inserting data by selecting data from other tables. This is a very common way to populate a table from existing data. The basic INSERT statement has the same syntax as a relational database's INSERT. However, Hive has improved its INSERT statement by supporting OVERWRITE, multiple INSERT, dynamic partition INSERT, as well as using INSERT to files. The following are a few examples:

  • The following is a regular INSERT from the SELECT statement:

    --Check the target table, which is empty.
    jdbc:hive2://> SELECT name, work_place, sex_age 
    . . . . . . .> FROM employee;
    +-------------+-------------------+----------------+
    |employee.name|employee.work_place|employee.sex_age|
    +-------------+-------------------+----------------+
    +-------------+-------------------+----------------+
    No rows selected (0.115 seconds)
    
    --Populate data from SELECT
    jdbc:hive2://> INSERT INTO...