Equality Joins With One Join Column

• R S is a common operation. The cross product is too large. Hence, performing R S and then a selection is too inefficient.

• Assume: M pages in R, pR tuples per page, N pages in S, pS tuples per page.

  • In our examples, R is Person and S is Purchase.

• Cost metric: # of I/Os. We will ignore output costs.

SELECT *

FROM Person R, Purchase S

WHERE R.name=S.buyer

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