whilst with those 2 simple ones it might seem like it makes no difference, do the same query and watch your ram usage, there is a large difference, (WITHOUT THE EXPLAIN), you will see a difference, becasue the SELECT * is loading it ALL in memory, where as the SELECT postid, ONLY loads the postid, and thus is alot more optimal,
if you look at the code and read the optimization guides for MySQL you will see why doing * is a very bad idea
easy way of explaining it
i want to find how many wheels are on my car, so what ill do is take my car apart, take all the parts, and put them in piles, and then count them all up, and then take the part i want out, and do another count on that, or i could take the wheels of my car and just count them
which will take less time, less room, and be better for me ????
--------------- Added [DATE]1193301090[/DATE] at [TIME]1193301090[/TIME] ---------------
either this is being lookd into, or vB dont seem to want to admit its mistakes ??
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