Multiple choice technology databases

At a minimum, how many join conditions should be there to avoid a Cartesian join if there are three tables in the FROM clause?

  1. 1

  2. 2

  3. 3

  4. There is no minimum.
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B Correct answer
Explanation

When joining three tables, you need at least 2 join conditions to avoid a Cartesian product. Each join condition connects two tables, so for N tables you need N-1 join conditions. With only 1 join condition for 3 tables, the third table would not be properly linked, creating a Cartesian product with the unjoined portion.

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