Filtering selections on mutiple levels

[tmd63]

I am trying to make a simple database which has a number of levels but a single input form.
There are 4 tables; Class, sub-class, category and data
There are a number of sub-class entries for a single class entry, a number of categories for each sub-class and a number of data entries for each category.
I have a form that uses combo boxes to show the full range of data for each data entry (class, sub-class, category and single data per form page).
But when I try to add a new data entry, the first selection is the class, but this appears to add a new entry in sub-class instead of allowing me to select the correct sub-class that is already entered (new sub-classes would be created separately). This then is refusing to continue as it states there is a blank entry in the sub-class.
Can anyone help as to how to create this?

[aytee111]

Not sure that I am following your process. Is it like this? Select class, requery sub-class combobox, select sub-class, requery category combobox, show data. Make sure that these comboboxes are unbound controls.

[tmd63]

yes. That is the flow. But if I just cycle through the previous items created. Unbound boxes do not appear to display the correct items.
The combo box appeared to show the correct Class, but stored the Class table reference as the name instead. So Class ID 1 was Anything, Class ID 2 was Another, Class ID 3 was 1 (this was being added as a new item instead of selecting 'Anything').

[tmd63]

I have now changed the flow. Instead of cascading the data. I put the reference link ID in the Data table instead, so my data table has 'Data',Class_ID, Sub-class_ID, Category_ID all stored in one table.

[aytee111]

Can you post your database? Then I can see what is happening here. Or a small sample of this.