Computed Values in Extra Queries

You may use extra queries to show the result of computations. Using this facility, you may display the number of computers of a particular model, for example. That is, use the extra query to compute a value for each visible record in a box.

To compute the number of tours that last a particular number of days, you may write the following query:

SELECT   COUNT(num_days) "Number of days"

FROM     FROM     schedtour_c, tour

RELATE   c "SUBJECT TO" h

As the query is performed once for each record in the box, you do not need a GROUP BY clause.

USoft Developer cannot retrieve a field prompt for this field from the repository. If you do not provide one yourself, it uses "COUNT(num_days)".