IT Operations - Data Structures, Software and Databases

Question 1

Data structures in accounting systems

Answer 1

All info and instructions used in IT are executed in binary code - 0s and 1s

1) Bit - individual 0 or 1
2) Byte - group, usually 8 bits, that are used to represent alphabetic and numeric characters. ASCII and EBCIDIC 2 most common

3)Field - group of bytes identifying a characteristic of an entity - date, text,number are common

4) Record - group of related fields describing an individual instance of entity (customer, specific invoice)
5) File - collection of records for one specific entity (tables)
6) Databae - set of logically related files

Except for “file” the words get longer as the units get bigger:

Question 2

Software

Answer 2

Computer software in 3 categories

1) Systems software - Programs that run the computer and support system
A)operating system
B)database mangement system (DBMS)
C)Data communication software
D)Utility programs

Question 3

2 Programming Languages

Answer 3

1. All software is created using programming languages. They consist of sets of instructions and a syntax that determines how the instructions can be put together. Types and examples of programming languages include:
   a. High-level, general purpose languages, such as the C programming language.
   b. Object-oriented languages such as C++, which are used to design modular, reusable software.
   c. Integrated development environments, such as Java, which provide templates that can be used to automatically generate code.
   d. Hypertext Markup Language (HTML), a tagging language, discussed in the lesson on the internet.
   e. Scripting languages, such as PERL or Python, which are used to add functionality to webpages.
   f. Fourth-generation programming languages, which are often used in database systems. An example command might be, “FIND ALL RECORDS WHERE ZIPCODE = 40703”.
   g. Low-level languages (e.g., assembler or machine) have code that is similar to a computer’s instruction set architecture.

Question 4

3 Application Software

Answer 4

Diverse group of end-user programs that accomplish user objectives

Question 5

Software Licensing

Answer 5

Organizations should have policies and procedures to ensure they comply with software copyright law

Question 6

Databases

Answer 6

Set of logically related files; characterizes by the way data relationships are established and the way it is implemented across organization

Question 7

Database mangement system

Answer 7

System for reading and managing a well-structured database. “middle-ware” program that interacts with the database application and the operating system to define the database, enter transactions into the database, and extract information from the database; the DBMS uses three special languages to accomplish these objectives:

1) Data definition language (DDL) - Allows the definition of tables and fields and relationships among tables
2) Data manipulation language (DML) - allows user to add new records, delete, update
3) Data Query language (DQL) - Extract information from database; using GUI to drag and drop into a query grid = query by example QBE

Database controls - DBMS should have following controls:

a. Concurrent access issues management, e.g., control multiple users attempting to access the same file or record
b. Access controls, i.e., tables that specify who can access what data within the system
c. Data definition standards, e.g., determine and enforce what data elements must be entered and which are optional
d. Backup and recovery procedures to ensure integrity in the event of system errors or outages
e. Update privileges that define who, and when, the data can and should be updated
f. Data elements and relationships controls to ensure data accuracy, completeness, and consistency