acct 307 exam 2

bit

;smallest unit of data; value of 0 or 1 - Binary digit

byte

8 digits

data hierarchy

bit → byte → data field → record → file → database

character

combination of bits forming a letter/number

field

group of characters representing an attribute (columns)

record

group of fields about one entity (rows)

file (table)

collection of related records

2 types of files

• transaction file

• master file

database

collection of related tables; collection of organized data that can be accessed by users & computer apps; tables are linked via attributes

relational database

group of related two-dimensional tables related through keys

DBMS (Database Management Systems)

stores, organizes, retrieves, & manages data efficiently

database keys

• primary key

• secondary key

• composite key

• foreign key

primary key

uniquely identifies each record

secondary key

used for searching/sorting

foreign key

field that links to a primary key in another table; non-key attributes; does'n’t have to exist in every table

composite key

multiple fields used together as a primary key

non-key attribute

anything that is not a primary key

transaction file

stores individual transactions

master file

stores cumulative data about an organizations resources (inventory) and agents (customers)

• updated to reflect the effect of specific transactions

record structure

specific data fields within a record of a database table

data dictionary

data file about the data itself which contains metadata and describes the data fields in each database record

administration

supervises the design, development, & installation of a large database system & responsible for maintaining, securing, & changing the database

concurrency control

protects records from errors when multiple users access the same file record simultaneously

ER

entity relationship (diagram)

entity

object you store data about

relationship

connection between entities

attributes

characteristics of entity

entities symbol

rectangles

attributes symbol

ovals

relationships symbol

lines

REA stands for…

resources, events, agents

REA data model

a special type of ER diagram; R,E, and A are entities

resource

economic value (cash, inventory) (A/R is an asset but NOT a ____)

event

business or economic event (sale, receive cash)

agent

internal agent; sales person and exteernal agent;customer

basic assumption for REA model

business events affect firm resources and involve agents who participate in the event

developing a database

1. identify the events about which management wants to collect information

2. identify resources & agents

3. identify cardinalities of relationships

4. create E-R diagrams

5. identify attributes of entities

6. create tables and records in a database

   1. each distinct entity will become a table

   2. additional tables are required for N:N relationships

normalization

methodology ensuring attributes are stored in most appropriate tables

• promotes accuracy & redundancy

Levels

• first normal form

• second normal form

• third normal firm

first normal form (1NF)

removing any repeating groups

• all data fields are singular

• each attribute has one value

second normal form (2 NF)

remove any partial dependencies

• it is in 1 NF

• all data items depend on primary record key

third normal form (3NF)

remove any transitive dependencies

• it is in 2 NF

• does not contain transitive dependencies

• one non-key attribute A does not determine another non-key attribute B

3 anomalies from unnormalized data

• update anomaly

• insert anomaly

• deletion anamoly

cardinality

describes the nature of the relationship between 2 entities

• indicates how many instances of one entity can be linked to a specific instance of another entity OR the max # of one entity that can occur given its relationship to another entity

give event

decreases resources

get event

increases resources

commitment event

does NOT immediately affect resources

economic duality

link between give & get events

rule 1

every event must be linked to at least 1 resource entity

rule 2

every event entity must be linked to at least one other event entity

rule 3

every event entity must be linked to at least 2 participating agents (1 external, 1 internal)

one to one

one record ←→ one record

one to many

one record → many records

many to many

many records ←→many records (needs linking table)

referential integrity

foreign key must match a primary key

select query

retrieves data

action query

updates or deletes data

DDL

defines database structure

DML

manipulates data

schema

entire database structure

subschema

subset of database

dynaset

dynamic subset of data from query

ERP

enterprise resource planning

integration

combines all business functions

centralized database

stores data once for entire company

benefits of ERP

better decisions, less redundancy, improved effieciency

costs of ERP

expensive, training, implementation risk

LAN

small/local network

WAN

large/global netwrok

TCP/IP

controls data transmission

XBRL

standard formatting for financial reporting

firewall

blocks unauthorized access

VPN

secure connection over public network

encryption

scrambles data (fullerton→ hoowrxyzh)

internal control

policies to protect assets & ensure accuracy

COSO components

1. control environment

2. risk assessment

3. control activities

4. information & communication

5. monitoring

segregation of duties

separate responsibilities

preventive control

stops errors before

detective control

finds errors after

corrective control

fixes errors

general controls

protect entire system

application controls

specific to transactions

input controls

ensure data accuracy

processing controls

ensure correct processing

output controls

ensure correct output

batch total

summarizes batch data

audit trail

tracks transaction flow

the basic unit of information on a computer file of accounting data is a(n):

a) inventory part number

b) data field

c) computer record

d) bit

bit

all of the following are items within the data hierarchy except:

a) database

b) data field

c) record

d) all of these items are part of the data hierarchy

all of these items are part of the data hierarchy

the data item which uniquely identifies a computer record in an AIS database table is called the:

a) pointer address

b) primary key

c) employee number

d) header label

e) foreign key

primary key

the best choice for the primary key in an “Employees” table would be his or her:

a) last name

b) first name

c) phone number

d) employee number

employee number

the foreign key in one database table will always be a ___ key in a linked table

a) secondary key

b) domestic key

c) primary key

d) all of these are true

primary key

a data dictionary:

is usually a computer file that maintains descriptive information about the data items of an accounting information system

difference between REA model and and traditional accounting systems

REA databases tend to store info. about resources, events or agents that do not immediately affect the financial statements of a company

which of these would be an example of a “resource” in the REA framework?

a) equipment

b) inventory

c) cash

d) all of these are possible examples of resources

all of these are possible examples of resources

in the REA framework, which of these would be record as an economic event(something that directly afffects financial statements)?

a) prepare invoices

b) prepare shipping documents

c) buying a piece of equipment for cash

d) all of these would be recorded as economic events

buying a piece of equipment for cash

in the REA framework, a database designer should create a ___ for each entity

a) record

b) table

c) secondary key

d) all of these

table

the purpose of the E-R model is to help database designers

a) identify data redundancies

b) create databases in third normal form

c) design databases and depict data relationships

d) answer structured queries about the data in accounting databases

design databases and depict data relationships

within a database context, the relationship between “natural parent” and “child” would most likely be

a) one-to-one

b) one-to many

c) many-to-one

d) many-to-many

one-to-many

a typical example of a “one-to-many” relationship is

a) customer to sales

b) inventory items to sales orders

c) sales orders and salesperson

d) none of the above

customer to sales

in an E-R model created using the REA framework, a customer would often be linked to sales with a relationship that is

a) direct between the customer and sales

b) indirect through a cash resources

c) indirect through an employee agent

d) indirect through inventory resource

direct between the customer and sales