Union query to add (All) to combobox not working properly - Microsoft Community

hi ,

i got union query meant add value (all) in combobx 2 columns, bound column 1

column 0;2

select tblcategories.categoryid, tblcategories.categoryname
tblcategories  
union select null as  filter, "(all)" catname tblcategories
 where (((tblcategories.isactivecategory)=yes));

running query right result. can see (all) in combo list. when click value (all) combo goes blank (the value (all) never displayed)

what doing wrong?

thanks

null never equal -- not -- when choose "(all)" list, setting combo's value null, value no longer equals value in list.

i think make work way want, you'll have use value other null represent "(all)"; maybe 0 or -1, if no categoryid equal 1 of values.

Office / Access / Other/unknown / Office 2010