Chapter 10

_________ refers to the range of activities involved in extracting data from a database

• Query Optimization
• Query Processing
• Parsing
• Query Evaluation

The steps involved in processing __________

• Parsing and translation
• Optimization
• Evaluation
• All of these

____________ is the process of selecting the most efficient query-evaluation plan from among the many strategies usually possible for processing a given query, especially if the query is complex.

• Query Processing
• Regulary Expression
• Query Optimization
• SQL

What is true about query optimization?

• The cost of evaluating a query can vary depending on its type.
• The evaluation plan is built by the system, so the user need not focus on writing their query efficiently.
• An efficient query evaluation plan is generated by a database system, which minimizes its costs.
• A, B and C

If the query was expressed in terms of a view, the _____ phase also replaces all uses of the view by the relational-algebra expression that defines the view.

• Pairing
• Parsing
• Translation
• Evaluation

The optimizer needs to generate alternative plans that produce the ___________ as the given expression, and to choose the least-costly one.

• partially different result
• rows as result
• columns as result
• same result

Which statement is used to revoke an authorization?

• Revoke
• Modify
• Alter
• Define

 Collections of operations that form a single logical unit of work are called _______.

• Views
• Networks
• Units
• Transactions

_______________ is a technique of granting permission to authorized user to carry out particular transaction

• Integrity
• Productivity
• Security
• Authorization

Which form of Authorization allows the user only to read data?

• Update Access
• Read Access
• Insert Access
• Both A and B