We Do Hadoop Contents Cheat Sheet Hive for SQL Users 1 2 3 Additional Resources Query, Metadata Current SQL Compatibility, Command Line, Hive Shell If you’re already a SQL user then working with Hadoop may be a little easier than you think, thanks to Apache Hive. Apache Hive is data warehouse infrastructure built on top of Apache™ Hadoop® for providing data summarization, ad hoc query, and analysis of large datasets. It provides a mechanism to project structure onto the data in Hadoop and to query that data using a SQL-like language called HiveQL (HQL). Use this handy cheat sheet (based on this original MySQL cheat sheet) to get going with Hive and Hadoop. Additional Resources Learn to become fluent in Apache Hive with the Hive Language Manual: https://cwiki.apache.org/confluence/display/Hive/LanguageManual Get in the Hortonworks Sandbox and try out Hadoop with interactive tutorials: http://hortonworks.com/sandbox Register today for Apache Hadoop Training and Certification at Hortonworks University: http://hortonworks.com/training Twitter: twitter.com/hortonworks Facebook: facebook.com/hortonworks International: 1.408.916.4121 www.hortonworks.com We Do Hadoop Query Function MySQL HiveQL Retrieving information SELECT from_columns FROM table WHERE conditions; SELECT from_columns FROM table WHERE conditions; All values SELECT * FROM table; SELECT * FROM table; Some values SELECT * FROM table WHERE rec_name = “value”; SELECT * FROM table WHERE rec_name = "value"; Multiple criteria SELECT * FROM table WHERE rec1=”value1” AND rec2=”value2”; SELECT * FROM TABLE WHERE rec1 = "value1" AND rec2 = "value2"; Selecting specific columns SELECT column_name FROM table; SELECT column_name FROM table; Retrieving unique output records SELECT DISTINCT column_name FROM table; SELECT DISTINCT column_name FROM table; Sorting SELECT col1, col2 FROM table ORDER BY col2; SELECT col1, col2 FROM table ORDER BY col2; Sorting backward SELECT col1, col2 FROM

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