MIS 380 FINAL

Denormalization _____.

- requires a modification of the logical database design result - introduces data redundancy - can improve database performance - avoids joins

What causes the basic incompatibility between current third generation programming languages and database processing with SQL?

3GLs process a single record while SQL processes a set of records.

What is the comparison operator for the Between operator?

>=and<=

What service does ADO provide?

A comprehensive front end to OLE DB

Which of the following is true regarding adding indexes to a relational database?

Adding too many indexes can slow overall performance if the data is highly volatile

An ODBC driver provides what service for an IS application?

Allows different languages to connect to various DBMSs

What is the advantage of using an XSD file over a DTD file?

An XSD file is itself an XML file

The most common data indexing in use today is the

B+ tree index

Which of the following aggregate functions CANNOT work on computed fields? Sum, Count, Avg, min, max

COUNT

What are aggregate functions?

Count, Avg, Max, Min, Sum

The keyword 'distinct' is used to do what?

Eliminate duplicate rows

What does the _symbol mean when using the LIKE operator and comparing a pattern or substring?

Exactly one character is skipped

What does the acronym XML stand for?

Extensible Markup Language

The two clauses that can be used to describe JOIN conditions are the ___clause & the ____clause

FROM clause & WHERE clause

What services does OLE DB provide?

Interfaces to both relational and non-relational databases

What does ODBC stand for?

Open database connectivity

What is the primary purpose of a data cube?

Provide aggregate data along specific dimensions

Data synchronization is required for what types of distributed databases?

Replicated databases

What are the three most common SQL clauses

SELECT, FROM, WHERE

Aggregate functions can appear in which clauses of an SQL query?

SELECT, HAVING

Security attacks on a database to access unauthorized data by spoofing the SQL statements is referred to as _______.

SQL Injection Attacks

A JOIN statement will always contain?

Two tables and a join on condition

Which of the following lists gives the order of execution of an SQL Statement by the DBMS? a. FROM, WHERE, SELECT b. FROM, SELECT, WHERE c. WHERE FROM SELECT d. SELECT FROM WHERE

a. FROM, WHERE, SELECT

Which of the following lists are change queries -- that change in the database? a. insert, update, delete b. add, change, delete c. insert, change, delete d. add, update, remove

a. insert, update, delete

Adding subset tables _____. a. None of the above b. avoids joins c. is one of the first physical design techniques that dshould be used to improve performance d. All of the above e. requires clustering files

a. none of the above

When performing OLAP processing on data in a data warehouse, the technique that is best for finding connections between attributes, where one attribute is often found paired with another attribute is called what?

association analysis

The main purpose of the "substituting foreign keys" physical design technique is to _____.

avoid joins

For any given application there are three basic services that must be provided. Which of the following is NOT one of the three? a. A data access function b. A network connection function c. A business function d. A display function

b. A network connection function

Which of the following lists includes items that can be included in the FROM clause? (check all that apply) a. Conditional statements, subqueries b. Table Names, literal constants c. Subqueries, Table names d. Table names, View names

c & d

Aggregate functions operate on what? a. Values on a single row b. Values across mult rows & columns c. Values across mult rows d. Values across mult columns

c. Values across multiple rows

In a conditional statement in the WHERE clause, which of the following statements is the correct way to test for 'boots' and heels' ?

category = 'boots' OR category = 'heels'

One purpose of defining a new, single field primary key to replace an existing multi-field primary key is _____. a.the multi-field key is clumsy to use as a foreign key in other tables b. None of the above c. the multi-field key cannot be indexed d. to avoid joins e. All of the above.

d. all of the above

which of the following lists gives the correct order of clauses in a well-formed SQL statement? a. Select, from, having, group by, where, order by b. Select, from, having, where, group by, order by c. select, from, where, order by, group by, having d. select, from, where, group by, having , order by

d. select, from, where, group by, having , order by

One way to distribute data to multiple locations is to make copies of the database at each location. What is this method called?

data replication

A star schema consists of what kinds of information?

fact tables and dimension tables

Rotational delay refers to the time it takes ____

for the data to arrive under the read/write head after the read/write head is switched on

Which of the following is NOT a function of an ODBC driver?

interpret SQL statements

In database technology what is the most important aspect of a transaction?

it is all or nothing processing

If an index involves a non-unique field of a file

it may return multiple records when it is used to access the file

The reason for performing physical database design is because the tables resulting from the logical database design _____.

may not perform well enough

Of the following, the one that is the least likely candidate to have an index built over it is a(n) _____.

non-search attribute

In a magnetic disk device, a cylinder consists of ___

one track from each recording surface, one above the other

The clustering files technique improves relational database performance by _____.

placing related rows of different tables near each other on the disk

An index built over a single field of a file ___

provides direct access to the file

Hashed files _____.

require synonym pointer chains when collisions occur

In the division remainder hashing algorithm _____.

the remainder points to the record location in the file

Of the following factors, the one least likely to affect database performance is ____

the speed of transferring data from the CPU to primary memory

A three-tier application that limits the functionality on the client layer to data entry and data display is sometimes called a(n) ________ _______ configuration.

thin client

The measure of the number of queries from simultaneous users that must be satisfied in a given period of time by the application set and the database that supports it is called _____.

throughput

All of the following are inputs into the physical database design process, except _____.

unnormalized data

Splitting off large text attributes into a separate table is a form of _____

vertical partitioning

When must an alias name be included within quote marks?

when it contains a space

Which of the following aggregate functions only work on numeric columns? SUM, COUNT, MAX, MIN, AVG

SUM & AVG

The data in a data mart is most frequently organized in what type of schema?

Star schema

What does SQL stand for?

Structured Query Language

In a vertically partitioned distributed database how is the data distributed across locations?

Tables have columns that are unique to each location

In a horizontally partitioned distributed database how is the data distributed across locations?

Tables have rows that are unique to each location

What is meant when a text field contains a null value?

The field has an undetermined data value

By adding the GROUP by clause to the query what happens to the rows?

The query is changed from rows to groups