This infographic by Datameer explains four ways Hadoop has changed analytics over traditional solutions.  Datameer is a data analytics solution built on Hadoop.

Apache Hadoop is optimized for analytical workloads. The MapReduce programming model is designed for analytics and the Hadoop file system is optimized for sequential data access. On the other hand, traditional RDMS databases are purpose built and optimized for record storage and retrieval with random read and write access. Thus, Hadoop is magnitudes faster for analytics workloads that need to scan through all the data like joins and aggregations.