A relational database management system (RDBMS) lies at the heart of jMetrik, and it is responsible for all of jMetrik’s data management capabilities. An RDBMS allows data and information about the data to be stored in multiple tables rather than a single fl at fi le. This feature increases the effi ciency of the program and provides a common framework for all data sets. You can think of jMetrik as a simplifi ed interface to the RDBMS that gives you easy access to the most essential procedures for data management. You can import and export data, select subsets of data, and delete variables or an entire table. jMetrik organizes data management into three types of operations: database operations, table operations, and variable operations. This chapter begins with a description of the default RDBMS and naming conventions enforced by jMetrik. It then describes all three types of database operations and gives step-by-step instructions for data management features in jMetrik. It also describes noteworthy limitations to data management and provides recommendations for best practices.