Question Let r and s be relations with no indices, and assume that the relations are not sorted. Assuming infinite memory, what is the lowest-cost way (in terms of I/O operations) to compute r ⋈ s? What is the amount of memory required for this algorithm?

ZBRRJF The Asker · Computer Science

Let r and s be relations with no indices, and assume that the relations are not
sorted. Assuming infinite memory, what is the lowest-cost way (in terms of I/O
operations) to compute r ⋈ s? What is the amount of memory required for
this algorithm?

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Step 1Let r and s be relations with no indices, and assume that the relations are notsorted. Assuming infinite memory, what is the lowest-cost way (in terms of I/Ooperations) to compute r ⋈ s? What is the amount of memory required forthis algorithm?explanation:Simply here the join operation is like the union operation on sets, suppose in a relation  r there are m elements and n elements in relation s, thenFirst, we must perform sorting of one of the array, since here the set size is not given we must compute thatand after that sort the smaller array or setnow for every element in the larger set if apply binary search in the smaller sorted array to soo if that element is thereif it is not there add it.Step 2The above task will takemin(mLogm + nLogm, mLogn + nLogn)which is the minimum. Amount of memory will be required (m+n).  ...