Restricting use of fields

[darrenN]

I have a booking database which has fields such as Name, Address, Telephone No etc. There are also 2 dropdown lists, one is a list of courses, the other a list of dates. The dates shown will depend on what course is chosen.

There is to be a maximum of 12 people on a course for each of the dates. If there are 12 records that have the same course and date then I want a message to say 'The course is fully booked' or soemthing along those lines, plus I would like it so that no more ecords with the same course and date can be chosen once there are 12 records.

Is this at all possible??

Thanks in advance.

DJN

[Kurt Knippel]

Setup a stored calc field (text result) = Course Name & Date.

Then setup a self relationship (Self by cCourseDate) cCourseDate::cCourseDate.

Finally setup another calc field with the error message = if ( count ( Self by cCourseDate::iOne ) >= 12, "This course is full", "Course open" )

[darrenN]

Hi, thanks for the help. I don't suppose that you could expand a bit on your answer unfortunately my skills and knowledge of FileMaker are quite limited.

[Kurt Knippel]

I am not sure how I can expand on my answer, without getting into a disertation on Filemaker basics. Pickup a book or two on Filemaker (and/or database design in general) and go through them, you will learn lots of stuff.

Basically what I explained to you was to setup a field to identify a certain combination that you want to track (the Course Name and Date). Then you setup a relationship into the same file by that field so that you can count all of the occurances of that combination. You do the actual counting in another calculation field, along with the appropriate checks and results to be displayed to the user.

Something that you really should do is to first design your program using either plain english or pseudo-code. Then you can convert this into the application development tool of choice. I feel that you have no idea how this would be accomplished in the first place, let alone how to do this in Filemaker specifically.

[darrenN]

Thanks for the pleasent reply, although you'll be happy to here that I worked it out in the end and my problem is now solved

[Kurt Knippel]

Great, glad to here it!