What is SQOOP ?
Sqoop is a tool designed to transfer data between Hadoop and relational databases or any NoSQL databases.
One can use Sqoop to import data from a relational database management system (RDBMS) such as MySQL or Oracle into the Hadoop Distributed File System (HDFS), transform the data in Hadoop MapReduce, and can also export the data back into an RDBMS.
Export can be used to put data from Hadoop to relational database.
How it’s Works ?
Sqoop uses JDBC connectors to connect to corresponding RDBMS or NoSQL databases
Sqoop will connect to database to get the table/column name and their datatypes from table metadata.Meanwhile Sqoop will not transfer any data between database to Hadoop it will querying the table views.
As per received metadata , Sqoop will create the java class and compile with Hadoop components. Squoop will connect to Hadoop cluster machine to submit the MapReduce(MR) job and Each MR will transfer the Table data’s
Here Sqoop act as supervisor for transferring the data instead of working as participant