I have a query which results in parents of pupils. I have a combo box with a union query which can be either "all" or a particular class. The idea is that by selecting a class, I will only have the parents of pupils in that class but if I select "all" then I will have all the parents in the school. However some parents have more than one child in the school so they come out a number of times in the query result when I select "all" from the combo. Is there any way that I can use the class field as a criteria to limit the parents of pupils in a particular class and yet when I select "all" from the combo it will show me all records but remove the parents which appear more than once (since they have children in a few classes)?

I know how to design the combobox for "all" etc but the problem is the filtering of duplicate parents
Thanks

Seems to me your database is not completely normalized.
However, if your "parents" query only retrieves the parents, try this adaption of your query:

SELECT
.....
UNION
SELECT blabla

becomes
SELECT
.....
UNION
SELECT DISTINCT PARENT

hth,

RV

Thanks for reply. My db is to my knowledge normalised. my parents query had to linked to the classlists in order to use that as a criteria. However I have solved it using 2 queries, firstly one which produced duplicate parents because the had multiple children in the school the I queried that query without the "class' field and set the query properties to unique values =yes. that filtered out duplicate parents. Yours I don't think would work because every record is distinct since the field for class is different
thanks again for your help
happy yn