The majority of my data work for the last dozen or so years has been via SQL and I am only concerned with sorting from a performance perspective, larger hardwar

The majority of my data work for the last dozen or so years has been via SQL and I am only concerned with sorting from a performance perspective, larger hardware (read minis and mainframes) usually have fully developed databases so the real work is done by the OS/db engine. It then becomes a game of ensuring adequate access paths and the like and using a query analyzer to see if what you put in executes as you like. I am more than amazed at the tricks a good query engine can pull but readily take advice it offers when a new index/access path is required. Since this covers the sorting the next issue is, making sure the project requests are asking for the right data. A lot of time we gain efficiency by analyzing what they want and making their request better fit that (see Bob, you really didn't need that million record request when all you wanted were this set here)