I see in an application developed by consultants here, that some dataflows are using a c=join(a*b) formula, and I can't find the difference with "c=a*b" when I test on my dataflows.
In some cases, "JOIN" appears in the db log as the algorithm, and some other time it's HBMP.
Does anyone knows what is the intended use of join algorithm ? What's the impact on the result ? on performance ?