Subtracting stock while issuing invoice

[tajurrehman]

HI ALL RESPECTED,

i am using Access 2010 and i am not able to subtract my stock inventory while creating sale invoice.

i am new here with you and i want to know easy way that how can i subtract my stock when i issuing sale invoice?

[June7]

Basically, you shouldn't. Saving aggregate data should be only in exceptional circumstances. Enter transaction records and calculate balances when needed. Review http://allenbrowne.com/AppInventory.html

[CJ_London]

short answer is you don't - maintaining a current stock quantity as a calculated field is fraught with possible problems.

At it's most basic you should have a table of transactions - stock in, stock out and adjustments. Then current stock is simply the sum of those transactions