Hadoop is a framework for storing and process data (big data) in several formats such CSV files. Hadoop is composed by several components such as distributed files system (HDFS) and a runtime environment that runs MapReduce programs for processing data physically distributed in datanodes.
On the other hand, a RDBMS (Relational database management system) store data in logical structures such tables, columns and rows. In order to read/write data, the user use the dialect SQL.
Hadoop and RDBMS are two different technologies used for storing and processing data. Hadoop is a distributed file system that can store large amounts of unstructured data across multiple servers. It is designed to handle big data and can scale horizontally as more data is added. RDBMS, on the other hand, is a relational database management system that stores data in tables with rows and columns. It is designed to handle structured data and is used for transactional processing.