abba (Spitfire)
I tried this way this evening. But after several minutes I gave up. I find it difficult for me to get focused at home. Yeah, the performance could be bad when using sub-query, especially when the data volume is large.

By the way, I like to write join conditions in the JOIN clause, instead of WHERE. I feel that things are clearer in this way.

Thanks! I've certainly learnt something today.
2001-11-14 -04:00
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