What is Apache Sqoop?

Apache Sqoop is a tool to bulk import/export data into Hadoop ecosystem (HDFS, HBase or Hive).

• works with number of databases and commercial data-warehouses.
• available as command line tool, can be used in java with passing appropriate arguments.
• graduated from the Incubator & became top-level-project in ASF.

Current version of Sqoop does a map-only job with all the transformation happen in map task. ( Sqoop2 will possibly have reduce task as well)

Fig : Sqoop 2 Architecture diagram taken from Cloudera.com

Example : 

alok@ubuntu:~/apache/sqoop-1.4.2$ bin/sqoop import --connect jdbc:mysql://<hostname>:3306/<dbname> --username <user> -P --driver com.mysql.jdbc.Driver --table <tablename> --hbase-table <hbase-tablename> --column-family <hbase-columnFamily> --hbase-create-table

or use it like this in your java programs - 

ArrayList<String> args = new ArrayList<String>();

args.add("--connect");

args.add("jdbc:mysql://<hostname>:3306/<dbname>");

args.add("--username");

args.add("<user>");

args.add("--driver");

args.add("com.mysql.jdbc.Driver");

args.add("--table");

args.add("<tablename>");

args.add("--hbase-table");

args.add("<hbase-tablename>");

args.add("--column-family");

args.add("<hbase-colFamilyName>");

args.add("--hbase-create-table");

args.add("--num-mappers");

args.add("2");

int ret = Sqoop.runTool(args.toArray(new String[args.size()]));

• Sqoop can write data directly to HDFS or HBase or Hive.
• It can also export data back to RDBMS tables from Hadoop.
• Sqoop integrates with Oozie, allowing you to schedule and automate import and export tasks.