Update Query Help Needed

[Siobhan]

Please can any of you help me?

My database is for a local garage and I have a booking table.
My booking table has the following fields;
Booking ID
Customer ID
Service Items ID
Booking Date - Long date format
Booking Time


Booking Duration
Total Booking Cost
Payment Due By

I am trying to create an update query which will update the "Payment Due By" from adding 7 days to the "Booking Date" however, when I try to update by doing [Booking Date] +7 nothing happens?

Please can you help me to complete this update query

[pbaldy]

It would help to see the SQL of your query, but if due date is always 7 days after the booking date, I wouldn't bother saving it and trying to keep it updated. You can calculate it on the fly.

[Siobhan]

This is what I have tried to do UPDATE tblBooking SET tblBooking.[Payment Due By] = [tblBooking]![Booking Date]=DateAdd("d",7,[tblBooking]![Booking Date]);

I have to show as screenshots that the query works as I have a dual purpose for it, its for the garage and part of my A Level Exam.
Thanks for your help

[pbaldy]

Oh, and personally I'd store the booking date and time in one field. It's easy enough to break them apart for display to the user. You'll likely have to join them together for queries anyway.

And hopefully you don't have those spaces in the field names. They aren't worth the bother in the long run.

[pbaldy]

With the two "=" in your SQL, you're setting the field to a True/False value based on the evaluation of the second one. You'd want:

UPDATE tblBooking SET [Payment Due By] = DateAdd("d",7,[Booking Date])

But again, storing what is essentially a calculated field violates the Normalization rules that I assume the professor discussed.

[Siobhan]

Thank you very much! It finally works