AIS Final

What are the problems of first normal form?

(1) Data redundancy (2) Insertion anomaly (3) Deletion anomaly

Cardinality relationships provide useful information about:

(1) the nature of the company being modeled (2) the business policies that it follows

Big data

A catch-all term for vast quantity of structured, semi structured, and unstructured data that are often available in real time or near real time.

What is third normal form (3NF)?

A database is in 3NF if it is in 2NF and contains no transitive dependencies (no relationship in which data field A determines data field B) Our goal is to create a database that is minimally in 3NF.

Normalization

A process of examining and arranging file data in a way that enables designers to avoid problems when files are used or modified later

SQL is an example of:

A query language

What are database management systems?

A separate software system that enables users to create, delete, access, query, view, analysis, or reorganize modify, and utilize database information more efficiently (Access, Alpha 5, dQuery, Lotus Approach)

An insert anomaly occurs when the database user cannot:

Add new data

In the REA model, the "A" stands for:

Agents

What is first normal form (1NF)?

All the records attributes (data fields) are well defined and the information can thus be stored in a flat file

An example of a validation rule is:

An input value must be between 0 and 40

What is the lowest level of information in a file?

Binary digit or bit

What is deletion anomaly?

Can cause the loss of accounting records and the destruction of audit trails

What is update anomaly?

Can generate conflicting and obsolete database values which make it had to have a good audit trail

What is insertion anomaly?

Can result in unrecorded transactions and incomplete audit trails

Database

Collection of files that contain all the information for an application

Record

Combines related data fields (employee payroll file)

Data field

Combines several characters of bytes (attribute, column, or field)

In the REA model, which of these would not be classified as an event?

Date of the office picnic

Foreign keys

Enable database records to reference one or more records in other files

Data manipulation language (DML)

Enables users to perform tasks such as querying, changing records, and deleting records

All of the following are examples of action queries except:

Find missing data query

To identify all those employees receiving payroll checks but who have no matching record in a payroll master file, you should use a(n):

Find unmatched records query

Flat files

Have no sequence or order to them, except perhaps chronological. Flat files make it almost impossible to find a particular record easily or use file data productively

What is second normal form (2NF)?

If it is in 1NF and all the data items in each record depend on the record's primary record key. This approach is more efficient design and eliminates much of the first files data redundancy (repetitive fields)

Which of these would not be a good primary key for a file of employee records?

Last name

Secondary keys

Non-unique identifiers Used for searching files for specific information

Which of these is not a cardinality between two database entities?

None-to-none

Which of these database tools is an accounting manager most likely to perform online, "drill-down" analyses?

OLAP

Data definition language (DDL)

Of a DBMS enables users to define the record structure of any particular database table

What is the typical cardinality between a customer and a purchase event?

One-to-many

The part of the data hierarchy that represents one instance of an entity is a:

Record

All of the following are examples of DBMSs except:

SQL

Volume

Sheer quantity and scale of data

Which of these does not characterize a typical database?

Simple systems

To construct a select query in Microsoft Access in which you want to satisfy two conditions simultaneously- that is, implement an And operation- you should:

Specify both criteria in separate fields of the criteria line of the query

What types of data can be stored in modern databases?

Text, graphics, video files, audio files, and programming code

A database is in third normal form (3NF) if it is second normal form and:

The data contain no transitive dependencies

Variety

The diversity of data that organization's create or collect

Veracity

The extent to which the data can be trusted for insights

The difference between (1) a database management system (DBMS) and (2) a database, is:

The first is program software, the second is proprietary data and related files

The difference between (1) using an update query and (2) updating a single record is:

The first updates all selected records, the second only affects one record

Velocity

The speed at which data are created

Within the context of databases, the term "concurrency" refers to the possibility that"

Two database users might want to access the same record at the same time

Primary keys

Unique for each record

To adjust the minimum wage of all payroll employees to the current federal level, you should use a(n):

Updated query

To link the records in a many-to-many relationship within a relational database:

You must create an intermediate "relationships" table