Question

If nested loop join is done on a per block basis rather than on a per tuple basis, it is called as

(a) Equi join

(b) Hash join

(c) Nested loop join

(d) Block nested loop join

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I want to ask this question from Join and Other Operations in section Query Processing and Optimization of RDBMS

Answer 1

Right option is (d) Block nested loop join

The explanation is: If nested loop join is done on a per block basis rather than on a per tuple basis, it is called as Block nested loop join. Within each pair of blocks, every tuple in one block is paired with every tuple in the other block to generate all possible combinations.