CS 331 Test 1 Practice

A subquery in which processing the inner query depends on data from the outer query is called a codependent query

False

Data integrity consists of powerful operations to manipulate data stored in relations.

False

Horizontal partitioning refers to the process of combining several smaller relations into a larger table.

False

The DELETE TABLE DDL command is used to remove a table from the database

False

The entity integrity rule states that a primary key attribute can be null.

False

The following command would work fine: insert into budget values 121,222,111;

False

The following query totals sales in state= 'MA' for each salesperson. Select salesperson_id, sum(sales) from salesperson group by salesperson_id having state = 'MA';

False

The following two SQL statements will produce different results. Select last_name, first_name from customer where state = 'MA' or state = 'NY' or state = 'NJ' or state = 'NH' or state = 'CT'; Select last_name, first_name from customer where state in ('MA','NY','NJ','NH','CT');

False

There can be multi-valued attributes in a relation.

False

When transforming a weak entity, one should create one relation with both the attributes of the strong entity and the attributes of the weak entity.

False

A candidate key is an attribute, or combination of attributes, that uniquely identifies a row in a relation.

True

A partial functional dependency is a functional dependency in which one or more non-key attributes are functionally dependent on part (but not all) of the primary key.

True

A transaction is the complete set of closely related update commands that must all be done, or none of them done, for the database to remain valid.

True

Clustering allows for adjacent secondary memory locations to contain rows from several tables.

True

Denormalization almost always leads to more storage space for raw data.

True

Joining tables or using a subquery may produce the same result.

True

Requirements for response time, data security, backup and recovery are all requirements for physical design.

True

The allowable range of values for a given attribute is part of the domain constraint.

True

When a regular entity type contains a multi-valued attribute, two relations are created.

True

When normalizing, the goal is to decompose relations with anomalies to produce smaller, well-structured relations.

True