Current information systems must deal with complex data management with regards on evolution over the time. There are several database systems with different data modelling principles, data handling and management, however concept of relational database is still most popular. The aim of this paper is to analyze and experimentally compare database systems Oracle and MySQL emphasizing the differences in syntax, semantics and performance characteristics. It consists of analysis of existing database systems, comparison of syntactic and semantic differences with regards on developed application functionality to transform commands to another system. Experimental part compares time consumption based on several characteristics.