Invisible Value on a form calculation

[JonathanS]

This is my first time using Acces so please be nice and speak in words of one sillible or less!

OK, Got a form to enter sales data on. calculation is set up to auto calculate the total using all sorts of things (delivery, tax etc) but will only show if all the fields are used.

EG:

Item 1 = Product 1
Units = 5
Price per Unit = £100
Total = £500 (auto calculate)

Nice and easy. However I've got 3 of the above such fields and if they only want one product the other two field will be blank.

I've tried setting the default values to 0 but still nothing.

Help please

 

[charityg]

in your sum equation, try using the Nz funtion:
total=nz(quantity,0)*nz(price,0)
this will automatically replace any null values with 0