Preventing duplicates in Dropdown

[oakridge]

I am currently using dropdowns to pull in secondary data into my main
datasource. Using SQL as the data source. I am pulling in a list of vendors
by name. The problem is that the Vendor Name may repeat in the list and I
only want the dropdown to show only one listing of any choice. Is there a
way to have it only show the selection once?

Thanks.

 

[oakridge]

Greg,

I entered in the following rule after viewing your example.

/dfs:myFields/dfs:dataFields/d:VENDOR-ADDRESS/@VEND-NAME[. = not(. =
.../preceding::dfs:myFields/dfs:dataFields/d:VENDOR-ADDRESS/@VEND-NAME) and .
= not(. = current()/..//dfs:myFields/dfs:dataFields/d:RTV-HEADER/@VEND-NAME)]

This appears to be correct but I am still getting errors. Does one have to
create an XML sheet for this from the XSN?