Jeff has posted about this type of update before. Basically, it's a time bomb waiting to explode, and when it does it will cause extreme slowness in your server.
Thanks for the heads up! In practice, I always use the JOIN format from my first example, so the table to be updated is always the first table. I never use the FROM table1,table2 WHERE format and I think it is being deprecated. But when looking at someone's legacy code I might not have known to check and change if you hadn't warned me. Another SQL-related death avoided. 🙂
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Against stupidity the gods themselves contend in vain. -- Friedrich Schiller
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