Add indices to your columns. Also, why do you need the COUNT(*)? Removing that if you don't need it will speed you significantly.
My criteria for good software:
  1. Does it work?
  2. Can someone else come in, make a change, and be reasonably certain no bugs were introduced?

In reply to Re^3: find difference in dates/items in same column by dragonchild
in thread find difference in dates/items in same column by zerocred

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