On Tue, Apr 13, 2010 at 05:58:41AM +0800, Colin Coe wrote: > Tomas, apologies for the original reply. > > My SQL skills are quite weak and doing the query wit joins did not > occur to me. Is using the joins more efficient? I can't see a > difference in the result returned when I run either of these queries.
Since there is a foreign key on rhnChannel(channel_arch_id) pointing to rhnChannelArch(id), the queries will return exactly the same results. There is nothing wrong with your syntax or your query. The only issue might be that when you or someone else will further tweak the query to for example return rhnChannelArch.label as well, with your query they might end up doing another inline select, instead of using the rhnChannelArch from the FROM list. And since the foreign key ensures that the cardinality of the result is not changed by joining with the rhnChannelArch table, it's actually a tiny bit better to do it the way Tomas has suggested. -- Jan Pazdziora Principal Software Engineer, Satellite Engineering, Red Hat _______________________________________________ Spacewalk-devel mailing list Spacewalk-devel@redhat.com https://www.redhat.com/mailman/listinfo/spacewalk-devel
