JRS (Java Relational System) is a Relational DBMS written in Java for didactic purposes

• to practice with SQL, using a simple multi-platform system (for Linux, Mac OS X, Windows),
• to practice with physical plans (access plans), that is how the DBMS executes the queries, as well as with the logical plans, that is how the DBMS translates queries in relational algebra,
• to experiment the effect on the physical plan generated of using different optimization techniques, and different phyical operators,
• to write and execute a query with a graphical editor, defining only a logical plan with the relational algebra, or only a physical plan with the JRS operators,
• to understand the components of a Relational DBMS, by discovering the interfaces among them,
• to experiment with data structures and algorithm to implement a Relational DBMS.