[Exim] Questions about database lookups

I'm a little confused on how exim handles database lookups.

When getting a sql generated list of items that are normally seperated
by colons, do I need to concat them with colons or can I use the list
raw. For example, would this work?:

domainlist local_domains = localhost : \
${lookup mysql{select unique domain from domains}}

Another example:

deny message = ${lookup mysql{select message \
    from blacklists where domain='$dnslist_domain'}}
   log_message = found in $dnslist_domain
   dnslists = ${lookup mysql{select unique domain from blacklist}}

--
Rossz