DBMS- Query, Transaction and Serurity Management - Practice Questions

Question 1

The internal query representation is usually a binary query tree.

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Question 2

Usually, heuristic rules are used in the form of query tree or query graph data structure.

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Question 3

Combining operations into a pipeline eliminates the cost of reading and writting temporary relations.

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Question 4

Execution plan is a series of query complication steps.

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Question 5

The emphasis of cost minimisation depends on  the size and type of database applications.

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Question 6

Query processing is the procedure of selecting the most appropriate plan that is used in responding to a database request

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Question 7

The cost of processing a query is usually dominated by secondary storage access, which is slow compared to memory access.

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Question 8

The success of estimating size and cost of intermediate relational algebra operations depends on the amount and accuracy of the statistical data information stored with the database management system (DBMS).

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Question 9

Transformation rules are used by the query optimiser to transform one relational algebra expression into an equivalent expression that is more efficient to execute.

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Question 10

A Query is contradictory if its predicate cannot be satisfied by any tuple in the relation(s).

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