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You don't go through entire loops everywhere because if there isn't a match in the first two tables, you don't have to check the match with the third table. It
by kebsup 2y ago
You don't go through entire loops everywhere because if there isn't a match in the first two tables, you don't have to check the match with the third table.
It's better to check A x C before A x B if you know that A x C has less matching rows, because the final loop will be shorter.
- bogdan-lab 2y agoAh, I see the numbers in the example are the numbers of matched rows, not a total number of rows... Make sense. I do not work with databases, did not know that you should pay attention to the order here.