What us the difference between hadoop and orcale db

Question

may I want to know difference of Hadoop and Oracle DB..In future which DB is highly preferrable..

Answer 1

You can find your answer here: https://stackoverflow.com/questions/19106255/hadoop-with-relational-database.
Oracle DB is a relational DB, so it has similar feature as MySQL.
Hadoop is suitable for batch processing, big data while relational DB is suitable for Online Analytical Processing (OLAP). They serve different purposes.