Jeff Moden (9/12/2010)
The "best plan" is dictated only by four things and only two of those really matter where performance is concerned...4. Code - This is where the true performance lies. Without doing this correctly, nothing else matters. Not hardware, not design, and usually not indexes. Write code the right way at all times. If it takes you too much time, then you need to get better at writing good code. 😛 The only way you can do that is to practice. A LOT! 😉
In some cases, the Database Tuning Advisor will suggest minor revisions to the T-SQL it's analyzing, like replacing a paramerized sp_executesql call with a straight SQL statement. I'm sure it could be made smart enough to recognize when someone is using a cursor or while loop to do something like populate a column with a comma seperated list of values, and then suggest they use a FOR XML sub-query instead, or it could simply advise them to do it on the front end. It could also suggest the removal of hints that have proven unbenefitial or the removal of unneeded distinct clauses (by confirming the presence of unique keys and join types).
"Do not seek to follow in the footsteps of the wise. Instead, seek what they sought." - Matsuo Basho