Crystal Reports 10: The Complete Reference

Overview

There are many situations in which the database you initially developed a report against will change. Perhaps the database is in a state of flux and will be changing dynamically as your report design proceeds. Or, you may develop a report against a test database and then change the report to point to a production database later. Possibly the database has been moved to a different server for network efficiency. Or you may determine that a different database driver should be used to connect to the database. For true flexibility, you need to be able to accommodate these changes easily, so that you don t have to re-create any features or functions of your report just because the database has changed.

With some of these database changes, the database designer or administrator may rename fields. When Crystal Reports detects these changes, it gives you the opportunity to change the field references inside your report, so the new field names can be automatically associated with the previous field names . This field mapping prevents you from having to add fields to the report again or modify formulas that refer to changed fields.

In addition to the Database Expert, which is discussed in Chapter 16, Crystal Reports provides three functions for efficient management of database changes:

• Verifying the database

• Setting the Datasource location

• Mapping fields

When you use either of the first two functions, and Crystal Reports detects changes that it is unable to resolve, such as field name changes or deletions, the field mapping function is automatically displayed.