A coded set of tables describing this information & stored in a computer system on direct access devices is called a SCHEMA. Which will describe the data aggregate data types & records. All references to data within the program will be for this description, which is known as SUBSCHEMA.

The different types DataBase organizations are

1.���� Hierarchical Model

2.���� Network Model

3.���� Relational Model

�

In relational model, rows are known as tuples & columns are known as Attributes. A code is an ordered collection of symbols designed to provide unique identification of an entity or attribute. The main purpose of codes is to facilitate the identification & retrieval of items of information from system.

Different types of coding system are

1.���� Classification code

2.���� Function code

3.���� Card code

4.���� Sequence code

5.���� Significant digit subset code

6.���� Mnemonic code

7.���� Acronym

�

System Development & Implementation

Two important phases of development are:

1.���� External development: This deals with the implementation, planning, preparation of manuals, in house training & equipment acquisition & installing.

2.���� Internal Development: Software development & performance testing are part of Internal development.

�

Major activities at System Development phase are

1.���� Implementation & Planning

�������� Plan to test computer program component as individual & integrated.

�������� Personnel training

�������� Conversion plans to convert to manual to automated.

2.���� Software development phase, preparing flow chart & pseudocode

3.���� User review

4.���� Equipment acquisition

5.���� Coding, debugging & unit testing

6.���� System testing

7.���� Manual preparation

8.���� Personnel training

9.���� UAT

�

Prototype is having two major advantages as

1)���� Its clarifies the all assumptions & issues with user requirements

2)���� It verifies the feasibility of system design.

�

The major criteria for hardware/software selection are

1.���� Define the capabilities that make sense to business

2.���� Specify the magnitude of the problem

3.���� Asses the competence of in-house staff

4.���� H/w & s/w should be considered as package

5.���� Specify a time frame for selection process

6.���� Provide user indoctrination.

�

Selection process will consists of� several steps.

1.���� Requirement analysis

2.���� System specifications

3.���� Request for proposal

4.���� Evaluation & validation

5.���� Vendor selection

�

Software selection depends on two streams like Customized & readymade, The main criteria for selecting software are

Benchmarking is a evaluation technique where the software purchaser compare the software with other to find the best of Speed & cost for his business.

To select a language, main criteria are

1.���� Volume of data

2.���� Complexity of processing

3.���� Compatibility with other systems

4.���� Types of i/p & o/p

5.���� Development efforts

�

Quality factor for SDLC

Quality Assurance for Software using

1)���� Testing

2)���� Verification & Validation

3)���� Certification

�

Three Reliability approaches are

1)���� Error avoidance

2)���� Error detection & correction

3)���� Error tolerance

�

Levels of testing are

1.���� Unit testing

2.���� System testing

�������� Program testing

�������� String testing

�������� System testing

�������� System documentation

3.���� UAT

4.���� Some other special types of testing are

System control is used to achieve

Types of system control are

1.���� External control:� like laws, regulations procedures & policies outside the scope of the system which affect the operations of the system

2.���� Internal controls are basically plans, procedures, Guideline, rules & checks under which a system must function.

�

Good documentation means

1.���� Availability

2.���� Objectivity

3.���� Cross referable

4.���� Easy to maintain

5.���� Completeness

�

Types of documentation are

1.���� Program documentation

2.���� Operation

3.���� User

4.���� Management

5.���� Systems

�

Software design & documentation Tools are

1.���� Structured flow chart which will contain flow charts for

�������� Process

�������� Decision

�������� Iteration

2.���� HIPO diagram

3.���� Warnier/Orr diagrams

�

Training should be given to two different categories of people,

1.���� System operator, persons who take care of systems

2.���� System user, persons who uses the system to enter data.

�

Training methods that can be used are

1.���� Vendor & In service

2.���� In house

�

There are� 4 main conversion method to replace a old system to new system,

1.���� parallel system

2.���� Direct

3.���� Pilot

4.���� Phase in

�

Main conversions plans to be

1.���� Site preparation

2.���� File & data conversion

�

Maintenance, different types are

1.���� Corrective : Repairing,� processing or performance failures or making alterations bcoz of� previous ill-defined problems

2.���� Adoption: changing the program function. Enhancing the performance or modify the programs.

�

Ecological & Green P C, two types of Green PC� which doesn't use chloro fluoro materials,

1.���� Light Green, consumes 25-30W, its spins IDE & shuts down display

2.���� Dark green, consumes 15-20W in standby mode, its spins IDE & shuts down display

�

Disaster recovery is of 4 types

1.���� Critical

2.���� Vital

3.���� Sensitive

4.���� Non-critical

�

To fight against the Disaster, we do have 5 different ways to overcome

1.���� Hot sites

2.���� Private hot-sites

3.���� Warm or cold sites

4.���� Service bureaus

5.���� Reciprocal agreements

�

Forms of Software piracy

1.���� Hard disk loading

2.���� Soft lifting

3.���� Software counterfeiting

4.���� Bulletin board piracy

5.���� Software rental

�

Computer crimes are classified as

1.���� Data related

2.���� Software related

3.���� Physical

�

Ergonomics essentially is the study of the relationship between the human being and the environmental factors affecting the physiological, psychological or anatomical state. The aims of Ergonomics are

1.���� To improve the efficiency of the interaction between the human & machine through enhancing the effectiveness & efficiency of human activities at work or at home.

2.���� To maintain the individuality of the worker by considerations of human welfare & human well being in the design procedure, namely in areas of health, safety, satisfaction & comfort of the worker.

�

Multimedia means a combination of Sound, text & graphics. Multimedia development work follows a path like���� planning/Design� >>>> Production >>>> Distribution. Presentation of graphics in multimedia is achieved thru many ways

1.���� Bitmaps

2.���� Vector images, object oriented format using lines & curves, ex CAD.

3.���� Animation

4.���� Morphing & warping

5.���� Digital Audio & video