A UFL is a collection of functions, written in a programming language such as Visual Basic, C , C# or Visual Fox Pro, and built into a COM server.Once you have created a UFL, the functions appear in Crystal's Formula Editor, and can be used in the same way as the built-in functions.
An alternative method would be to use the SQL command for updating the database, and use a regular table or view as the data source for the report, just as you would if you weren't using SQL commands.
In some cases, though, you might still need to provide a dummy SELECT statement within the SQL command, as CR will expect some data to be returned from the command, even if that data wasn't used in the report.
One way to do that is to place the INSERT, UPDATE or DELETE statements in the same SQL command as the SELECT statement.
However, not all databases will allow you to combine SQL statements in this way.
Keep in mind that SQL commands are executed as soon as you save them.
This means that the update will take place, not just when you run the report, but also every time you edit and save the command.An end user could Crystal's experts and wizards to filter and sort the data.But instead of showing the data in the usual tabular format, the report consists of a series of INSERT statements - one for each row - incorporating the values to be inserted.Broadly speaking, there are three ways in which you can give Crystal Reports the ability to update a database.The first option is to use CR's user function library (UFL) feature.You would then place the formula in, say, the report's header band so that it is called each time the report was executed.