OK. im am in charge of the store/stock room that hold the parts. I have made a table containing all the parts and the qty we have in stock, i have also made a table for the parts to be assigned to a certain vehicle and the qty.
I need the database to take the number of parts (eg 5 fuses) that i assign to a vehicle and take that ammount from the total number (eg 10 fuses) of parts automatically so that when i look on how many "fuses" are left. (5 fuses lwould appear on the parts databse)
You can turn your little table into a full-blown Inventory Control database if have a mind to do so. At the very least, though, you should have two tables, one Inventory Items table, and a Transaction Table. The Items table might have a column for item number, category (fuse), description (10 amp), and quantity on hand. The transaction table might contain columns for item number (with which you can make a relationship to the items table), transaction type (receiving, as on a PO, or issue to the floor), and a quantity. For every transaction, either incoming or outgoing, add or subtract the quantity to/from the quantity on hand field in the items table. Once you're familiar with the manual procedure, you can then automate it by using a form, queries, reports, etc.