# nptel pdf

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Q Consider a relation R(a, b, c) ordered on a non-key attribute b, and an index is maintained on attribute c. To evaluate the following expression, which is a better order of operation? σ(b=‘abc’∧c=12)(R)

A. First filter tuples using index on c and then search for b

B. First search tuples for the given value of b and then use index on c

C. The order of operation does not matter

0
d?
0
Yes plz explain

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