Conduct an organisation to using data analysis with Hadoop

Hadoop is free set of utilities, correct? So as usual there is no SLA and everything is at your own risk.  You need to create a manual for dummies how to use it. And then take the risks….

No big deal, I guess.  Just use SQL (what all your people should know if they work with DWHs) on top of Hadoop.  Apache Hive runs on top of Hadoop: “Apache Hive ™ data warehouse software facilitates reading, writing, and managing large datasets residing in distributed storage using SQL.”

If you are not ETL this new data source from the Hadoop clusters into the datawarehouse than Georg already has given you the answer.  But it beg to ask this question why not putting all data sources on Hadoop?

If the strategy is to make the Hadoop clusters the active platform for predictive data analytics that requires a different approach as now all data sources pertaining to eg. Customer ID can be loaded into the Hadoop clusters with harmonisation, while the datawarehouse function is more for compliance and BI, post mortem analysis.