Pls any body reply for this question.
Which circumstance does the optimizing choose a product join?
Thanks for advance

Answer Posted / yuvaevergreen

Product join in not desirable unless required as it involves
over usage and unnecessary usage of resources. The query
designer should always use conditions in the query or sub
queries to reduce the no of qualifying rows. This can be
easily observed by analyzing the execution plan. So TD
assumes "product join" when there are tables involved
without any condition. Example below,
SELECT * FROM A,B;
Since no filtering condition has been used, this results in
a product join.

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