This manual assumes that you have some basic knowledge of C++ and the Qt application development framework. If you need to learn more about C++ or Qt there are a vast number of C++ books available, and a small but increasing number of Qt books. Qt comes with extensive online documentation and many example applications that you can try.
The Enterprise Edition of Qt includes the Qt SQL module. In Chapter 6 "Creating Database Applications" we demonstrate how to build SQL applications with Qt Designer; this chapter requires some knowledge of SQL and relational databases.