Q. State true or false: Multiple equivalence rules can be used one after the other on a query

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Q. Which of the following information does the database system catalog store?

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Q. Most databases store the distribution of values for each attribute as a __________

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Q. What is the function of the equi-width histogram?

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Q. What kind of a sample must be used for statistical analysis?

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Q. The ________ SQL command generates statistics on a particular relation

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Q. The union of all records satisfying the individual simple conditions Oi is called as ________

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Q. The intersection of all records satisfying the individual simple conditions Oi is called as ________

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Q. State true or false: Estimation of the size of the result of a join is not possible

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Q. Size estimation can be done for which of the following processes?

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Q. The size of a _____ is simply V(A,r) where r is the relation and A is a distinct value

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Q. A ________ explores the space of all query evaluation plans that are equivalent to a given query.

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Q. What is the disadvantage of cost based optimizers?

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Q. A particular sort order is said to be _________ sort order if it could be useful for a later operation.

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Q. The rule that allows transformation of a logical operation to a physical operation is called

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Q. State true or false: Making multiple copies of the same sub-expressions must be avoided

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Q. Optimizers use __________ to reduce the cost of optimization.

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Q. The join orders where the right operand of each join is in one of the initial relations are called as ________

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Q. Caching and reuse of query plans is called as ________

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Q. What technique is used for the evaluation of a query with a nested sub query?

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