Nested loop join
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Two relations and are joined as follows:
For each tuple r in R do For each tuple s in S do If r and s satisfy the join condition Then output the tuple <r,s>
This algorithm will involve nr*bs+ br block transfers and nr+br seeks, where br and bs are number of blocks in relations R and S respectively, and nr is the number of tuples in relation R.
The algorithm runs in I/Os, where and is the number of tuples contained in and respectively and can easily be generalized to join any number of relations.
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