Many existing software applications involve complex application layer implemented in OO programming languages and at the same time use relational database systems as back-end data store. Modeling the whole system in a consistent manner will help developers and end users better understand the application. Application layer and database layer sometimes are tightly coupled together in some legacy systems; however, most people use UML and ER modeling to model these two layers respectively, which creates lots of inconsistencies. Database operations can?t be properly modeled using ER modeling. In this work we present an extension to UML Data Modeling Profile and use concrete examples to illustrate how to model relational database operations using UML. Atomic database operations are modeled based on our framework and are used as building blocks to model more complex database operations.