DB Interface Module User’s Guide : PART II Using the Basic Features : Chapter 7 The Data Model : Summary
Summary
SourcePro DB defines a three-layer data model, consisting of the database layer, the pointer layer, and the value layer.
• The database layer is not visible to applications. Database-dependent data types are used only within this layer.
• The pointer layer stores all data by pointer through class RWDBTBuffer<T>. Using this class, applications with special needs may access the internal storage layer directly.
• In the value layer, coding is done using C++ types, as well as RWCString, RWBasicUString, RWWString, RWDBMBString, RWDecimalPortable, RWDBBlob, RWDateTime, and RWDBDuration. These classes have broad applicability that is independent of database programming.
In transporting data to and from databases, SourcePro DB follows a strategy of early data binding.
Programmers can use RWDBValue directly to work with data whose type is unknown or unimportant.