[tomlock]

One thing to note here might be that if network is the bottleneck you'd likely be asked the opposite. In my experience if people pay attention to indexes/partitioning they can win dba's hearts, but dbas often don't explain these things because most people don't listen. So to them its easier to say "don't run complex queries".

[SOLAR_FIELDS]

Part of the problem with people paying attention to indexes/partitioning is that there's no very easy way to display that to the end user. A person knowledgeable in SQL can query the right tables to determine this but at that point you're pretty much thinking like a DBA in the first place. If major vendors had a nice visualization of such a thing built into the interaction tools like SSMS/SQL Developer/PGAdmin3 etc. then it might be easier (these might exist, I'm just not aware of them).

So yeah, the end result is DBA's give the generic "don't run SELECT * and use a WHERE clause when you're querying large tables"