ODBC does not make your application instantly portable to any database or data source that has ODBC support. Many layers of software are involved in the data retrieval process, and each layer adds its own restrictions.
The major component that makes an ODBC connection work is the ODBC driver. (See the ODBC Structure topic for more information.) The driver processes API function calls, submits SQL requests to a specific data source or DBMS, and returns results.
ODBC drivers are available from a variety of vendors and offer very different levels of support and performance. The sources of the data that the drivers connect to also offer very different capabilities in areas such as record locking, file operations, and transaction management.
These differences in performance and capability can have a large impact on your application. To assist you in choosing a driver, ACUCOBOL-GT conducts tests of individual drivers and publishes the names of drivers that pass our certification standards. As we complete the certification for a particular driver, we add it to our list and indicate that it conforms to a base level of functionality. We also give you specific information about the driver as it relates to Acu4GL for ODBC. This list is available on our World Wide Web site at http://www.acucorp.com.
Because there are so many driver manufacturers, database management systems, and non-database sources of data, all continually releasing new versions of their products, it is not possible for Acucorp to certify each one. For this reason, we also publish a list of user-tested drivers. Drivers on this list have been tested by Acucorp customers. Details about their experiences with the driver are indicated on the list.