What Are The Advantages And Disadvantages Of Hash Indices Relative To

1.	What Are The Advantages And Disadvantages Of Hash Indices Relative To B+-tree Indices? How Might The Type Of Index Available Influence The Choice Of A Query Processing Strategy?
Answer» Hash indices enable US to perform point LOOK up (eg. σA=r(relation)) operations very fast, but for range searches the B+-tree INDEX would be much more efficient. If there is a range query to be evaluated, and only a hash index is available, the better STRATEGY might be to perform a file scan rather than using that index. Hash indices enable us to perform point look up (eg. σA=r(relation)) operations very fast, but for range searches the B+-tree index would be much more efficient. If there is a range query to be evaluated, and only a hash index is available, the better strategy might be to perform a file scan rather than using that index.

What Are The Advantages And Disadvantages Of Hash Indices Relative To B+-tree Indices? How Might The Type Of Index Available Influence The Choice Of A Query Processing Strategy?

Answer»

Hash indices enable US to perform point LOOK up (eg. σA=r(relation)) operations very fast, but for range searches the B+-tree INDEX would be much more efficient. If there is a range query to be evaluated, and only a hash index is available, the better STRATEGY might be to perform a file scan rather than using that index.

Hash indices enable us to perform point look up (eg. σA=r(relation)) operations very fast, but for range searches the B+-tree index would be much more efficient. If there is a range query to be evaluated, and only a hash index is available, the better strategy might be to perform a file scan rather than using that index.

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