Global Variable

[Mute]

Hi,

hope sum1 can help me.

I am trying to create a simple stock control system.

I need to check stock levels of products. I need help in creating a field which automatically updates the product levels of items when they are ordered and sold.

I thort mayb I need to create global variables but i dont know how this is done.

If any1 can help it wud b much appreciated.

Thanx in advance