Many changes have been made to improve support for database application development in Delphi 2007 for Win32.
Unicode support has been added to the Oracle, Interbase, and MySQL dbExpress drivers.
New driver clients have been added: Interbase 2007 and MySQL 4.1 and 5.
A new dbExpress framework has been created. You can use this framework both to interface with existing drivers and to write new drivers by extending dbExpress framework's abstract classes. You can use the framework directly for both native and managed applications.
A delegate driver is a driver between the application and the actual driver. Delegate drivers allow for pre and post processing of all public methods and properties of the dbExpress 4 framework. Delegate drivers are useful for connection pooling, driver profiling, tracing, and auditing. Sample delegate drivers area provided.
The dbExpress VCL component's API has changed. Most applications are not affected by changes to the dbExpress VCL. However, there are some methods, properties, events, constants, and enums that were removed or replaced with equivalent functionality.
You can also use the dbExpress VCL components that are layered on top of the framework for both native and managed applications. There are some minor API changes in the VCL components to the TSQLConnection class (method changes), TSQLDataSet (new property), and data structures (some are removed or replaced). See dbExpress Framework Compatibility for more information.
The dbExpress driver framework:
- is written entirely in the Delphi language and allows drivers to be written in Delphi.
- uses strongly typed data access instead of pointers. For instance, the framework uses String types rather than pointers to strings.
- is single sourced. This means that a single copy of the source can be compiled with either the native DCC32 or managed DCCIL compilers.
- has only Abstract base classes that are used for drivers, connections, commands, readers, and so on.
- uses exception-based error handling rather than returning error codes.
