DB CS 331

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True

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

False

A part object that belongs to only one whole object and lives and dies with the whole object is called composting.

True

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

False

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

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

A transaction that requires reference to data at one or more nonlocal sites to satisfy the request is a global transaction.

True

Aggregation is a part-of relationship between a component object and an aggregate object.

True

CASE tool-generated information should be fed into repositories

True

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

False

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

True

Data localization involves transforming a query into fragments that explicitly reference data at one site.

True

Data reconciliation occurs in two stages, an initial load and subsequent updates.

True

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

False

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

True

JDBC is the industry standard call-level API for Java access to SQL databases

True

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

False

Object-oriented environments and relational environments have the same navigational model for accessing persistent data.

True

Object-oriented environments typically do not have an inherent, built-in concept of boundaries between transactions.

True

One of the primary differences between the while statement and the for statement is that in addition to a conditional expression, the for statement can also include code that initializes a counter and changes its value with each iteration.

True

Replication transparency s a design goal in distributed database systems, which says that even though a data item may be replicated at several nodes throughout the network, a user may treat the data item as if it were a single data item at a single node

True

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

True

Serialization is not a realistic method for storing large amounts of structured data

False

Static extract is a method of capturing only the changes that have occurred in the source data since the last capture.

False

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

False

The Information Resource Lexicon System (IRLS) is a computer software tool used to manage and control access to the information repository

True

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

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');

True

The major advantage of the data propagation approach to data integration is the near real-time cascading of data changes throughout the organization

False

There can be multivalued attributes in a relation

True

To keep your database from growing too large, you should choose the smallest data type possible for each field

AGGREGATE

To summarize data in a set of records, you use a family of functions called ____ functions.

True

Two-phase locking results in a growing phase where locks are acquired and a shrinking phase where locks are released

SELECT

What privilege allows the user to select records?

True

When a regular entity type contains a multivalued attribute, two relations are created.

True

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

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

With a two-phase commit strategy for synchronizing distributed data, committing a transaction is faster than if the originating location were able to work alone.


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