I have a table that holds all inventory in stock - CurrentInventory

This contains:

ItemID

ColourID

SizeID

Qty

There may be the same ItemID, with different ColourID, and different SizeID.

Eg:

Item 1, Colour 1, Size 1, Qty 5

Item 1, Colour 1, Size 2, Qty 5

Item 1, Colour 2, Size 1, Qty 5

Item 2, Colour 2, Size 1, Qty 5

I want to create a value list to be accessed from my Purchases section, that only lists the available ItemID, and then once that is selected, shows only available colours in the ColourID field, and so on.

How is this do-able? All the examples I have seen have 2-3 tables for the set up, but all the information of mine is stored in one table..

All the examples I have seen have 2-3 tables for the set up, but all the information of mine is stored in one table..

One would expect your example to have a table of Colors and a table of Sizes - otherwise the ColourID field must hold the actual color and the SizeID the actual size. If that's the case, you can still have your conditional value lists:

1. Define a relationship where:

Purchases::ItemID = Inventory::ItemID

2. Define a value list of AvailableColors, using values from Inventory::ColourID, include only related values starting from Purchases;

3. Repeat #2 for sizes.

One would expect your example to have a table of Colors and a table of Sizes - otherwise the ColourID field must hold the actual color and the SizeID the actual size. If that's the case, you can still have your conditional value lists:

1. Define a relationship where:

Purchases::ItemID = Inventory::ItemID

2. Define a value list of AvailableColors, using values from Inventory::ColourID, include only related values starting from Purchases;

3. Repeat #2 for sizes.

excellent!