Huwebes, Agosto 4, 2011

QUIZ 8


Quiz 8 - Database Management

1. Define the term, database, and explain how a database interacts with data
and information.

2. Describe file maintenance techniques (adding records, modifying records,
deleting records) and validation techniques.

3. Discuss the terms character, field, record, and file

4. Discuss the functions common to most database management systems:
data dictionary, file retrieval and maintenance, data security, and backup
and recovery.

5. Differentiate between a file processing approach and the database
approach.

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

7. Explain how to access Web databases.

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.

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

10. Discuss techniques to prevent unauthorized computer access and use
ANSWER:
1. Database -  is a collection of data organized so you can access, retrieve, and use it. Data is a raw facts while Information is a data that is organized and meaningful. Computers process data into information including a photograph, is entered and stored on the hard disk and extracts the member data from disk and lastly the receipt is created and printed.


2. File maintenance techniques - is a procedure that keep data current and add, change and delete (A,C, D), add new record when you obtain new data, change record to correct inaccurate data and update old data, records are deleted when it is no longer needed and some programs remove record immediately others flag record.

3. Field is a combination of one or more characters the smallest unit of data user accesses field name uniquely identifies each field, field size defines the maximum number of characters a field can contain and data type specifies kind of data field contains. Record are group of related fields the key field or primary key uniquely ientifies each record. And data file is collection of related records stored on disk.

4. Data dictionary contains ata about each file in database and each field within those files. Data security provides means to ensure only uathorized users can access data and access priviledges define activities that specific user or group of users can perform thus priviledges are the read-only priviledge wherein user can view data but cannot change it and full-update priviledges in which users can viewed and change data. Backup is a copy of the entire database.

5. File processing approach each department or area within organization has own set of files and records in one file may not relate to records in any other file and may have strenght as to reduced data redundancy, improved data integrity, shared data, easier access and reduced development time and its weaknesses like data redundancy same fields stored in multiple files and isolated data that are stored in a separate files so it is difficult to access. While database processing is an approach in which many programs and users can share data in database and secures data so only authorized users can access a certain data.

6. The four popular data models are the following relational database stores data in tables that consist of row and columns, each row has primary key and each columns has unique name it also stores data relationships and uses specialized terinology, object-oriented stores data in objects, can store more types of data, access data faster and programmers can refuse objects, example stores images, audio and video clips, engineering, architectural , and scientific designs, stores also documents such as schedules, calendars, manuals, menus and reports, and contains links and other documents lastly link to e-form on Webpage, and lastly multidimensional database stores data in dimensions also called hypercube, allow users to anlyze any view of data and can consolidate data much faster than relational database.

7. To access Web database by simply by filling in a form on a Web page usually resides on a database server, a computer that stores and provides access to a database.

8.

9. Guidelines for developing for developing database first you have to determine the purpose of the database, design the tables, in designing the tables fint on paper and each table should contain data about one subject, design the records and fields for each tables and be sure every record has a unique primary key, use separate fields for logically distinct items, do not create fields for information that can be derived from entries in other fields, allow enough space for each field and set default values for frequently entered data, and lastly determine the relationships among the tables or filesDatabase analyst focuses on meaning and usage of data, decides proper placement of fields, defines relationships, and identifies users' access privileges while Database administrator create and maintains data dictionary, manages database security, monitors database performance, and checks backup and recovery procedures.

10. Guidelines for developing a database first you have etermine the purpose of the database, second design the tables by fint on paper and each table should contain data about one subject, third, design the records and fields for each table and be sure every record has a unique primary key, use separate fields for logically distinct items, do not create fileds for information that can be derived from entries in other fields, allow enough space for each field and set default values for frequently entered data and the fourth one is to determine the relationships among the tables or files.

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