Quiz #8

1. Define the term, database, and explain how a database interacts with data and information.
- Database collection of data organized in a manner that allows access, retrieval, and use of that data.


2. Describe file maintenance techniques (adding records, modifying records, deleting records) and validation techniques.
- File Maintenance  refers to the procedures that keep data current.
- Adding Records users add new records to a file when they obtain new data Disc
- Modifying Records users modify a record to correct inaccurate data or update old data
- Deleting Records When a record no longer is needed, a user deletes it from a file
- Validation Techniques compares data with a set of rules or values to find out if the data is correct  

• Alphabetic/Numeric check
• Range check
• Consistency check
• Completeness check
• Check digit
• Other checks

3. Discuss the terms character, field, record, and file
- Characters numbers, letters, space, punctuation marks, or other symbols
- Field is a combination of one or more related characters
- Record is a group of related fields
- File is a collection of related records

4. Discuss the functions common to most database management systems: data dictionary, file retrieval and maintenance, data security, and backup and recovery.
-Data Dictionary contains data about each file in the database and each field in those files
-File Retrieval and Maintenance 
-Data Security 
-Back up and Recovery


5. Differentiate between a file processing approach and the database approach.
-   In a file processing system, each department or area within an organization has its own set of data files. The records in one file may not relate to the records in any other file. Two major weaknesses of file processing systems are redundant data (duplicated data) and isolated data. With a database approach, many programs and users share the data in a database. The database approach reduces data redundancy, improves data integrity, shares data, permits easier access, and reduces development time. A database, however, can be more complex than a file processing system, requiring special training and more computer memory, storage, and processing power than file processing systems. Data in a database also can be more vulnerable than data in file processing systems.

6. Describe characteristics of relational, object-oriented, and multidimensional databases.

-    A data model consists of rules and standards that define how the database organizes data. Three popular data models are relational, object-oriented, and multidimensional. A relational database stores data in tables that consist of rows and columns. A relational database developer refers to a file as a relation, a record as a tuple, and a field as an attribute. A relational database user refers to a file as a table, a record as a row, and a field as a column. A relationship is a link within the data in a relational database. Structured Query Language (SQL) allows users to manage, update, and retrieve data in a relational database. An object-oriented database (OODB) stores data in objects. An object is an item that contains data, as well as the actions that read or process the data. Applications appropriate for an object-oriented database include a multimedia database, a groupware database, a computer-aided design (CAD) database, a hypertext database, and a hypermedia database. Object-oriented databases often use an object query language (OQL) to manipulate and retrieve data. A multidimensional database stores data in dimensions. These multiple dimensions, sometimes known as a hypercube, allow users to access and analyze any view of the database data. No standard query language exists for multidimensional databases. One application that uses multi dimensional databases is a data warehouse, which is a huge database that stores and manages the data required to analyze historical and current transactions. A smaller version of a data warehouse is the data mart, which contains a database that helps a specific group or department make decisions.

7.Explain how to access Web databases.

-   To access data in a Web database, you fill in a form or enter search text on a Web page, which is the front end to the database. A Web database usually resides on a database server, which is a computer that stores and provides access to a database. One type of program that manages the sending and receiving of data between the front end and the database server is a CGI (Common Gateway Interface) script.

8. Define the term, computer security risks, and briefly describe the types of cybercrime perpetrators:

   hacker, cracker, script kiddie, corporate spy, unethical employee, cyberextortionist, and cyberterrorist. 

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9.  Identify database design guidelines and discuss the responsibilities of database analysts and administrators.

- A database analyst (DA), or data modeler, focuses on the meaning and usage of data. The DA decides on the placement of fields, defines data relationships, and identifies users' access privileges. A database administrator (DBA) requires a more technical inside view of the data. The DBA creates and maintains the data dictionary, manages database security, monitors database performance, and checks backup and recovery procedures. In small companies, one person often is both the DA and DBA. In larger companies, the responsibilities of the DA and DBA are split among two or more people.

10. Discuss techniques to prevent unauthorized computer access and use

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