Compare the nested-loop join and block-nested loop join, Database Management System

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Compare the Nested-loop join and block-nested loop join

Ans: Nested  loop join - It is costly as worst case cost, no. of block accesses needed is nr * bs + br  where bs and br denote no. of blocks containing  ns and nr tuples of relations S and R, relevant and in best case there will be br + bs block accesses

Block-nested-loop join - In worst case no. of block accesses is br*bs + br. In best case, br +bs block accesses will be needed.


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