If you have been using the Data Source Designer, at this point you have a SQL script which can
be refined manually.
Another possibility is that the whole design process has been skipped and you have
loaded your SQL script
directly into the code window from an external
text file.
In either case you have a script which can be edited at will. The "Try query"
button allows you to test if there are errors in it.
It is possible to define
parameters. Within DataTime, "parameters"
are simply placeholders, which will be substituted
with
arbitrary pieces of text provided by the user. It is convenient define "parameters" because this allows
you to change the result of the code execution.
For instance, when designing a ReportGrid, you can specify new values for the parameters. Or, a remote web user, with appropriate
permission, specified in the
metadata
database, can regenerate a report by overriding
the parameter values of the Data Sources which fed the ReportGrids contained in the
report.