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Computers are used in almost every field and profession to perform to perform a large number of useful activities. Technological innovation over the last two decided have not only increases the range of technically feasible applications they have also reduced costs so that computer provide a cost effective solution to far wider range of problem than computer provide a cost effective solution to a far wide range of problem than they did before. In business, bank to transfer funds electrically from one location to another use computers. Computers are used to control inventory, and computerized robots are used to wield parts together, paint and much more. With office automation the computer is used for word processing, electronic mail, voice storage and forwarding, facsimile and teleconferencing. In science and engineering, computers are unlocking the secrets of our universe. In business organization, computer easy maintain accounting system and payrole. In health care, computers are used to keep people in shape. In the military computers are used to help people locating oil and diagnosis of medical problem.

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                  Tayeb Ahmed Khan
                  ASA University of Bangladesh
The solo purpose of this project was to explore the application of
information technology in the production and the inventory management
system .of These two sections combine the heart of their operations.
Effective and efficient handling of the data generated in these areas can
bring huge improvement in their total performance. To equip them with
computerized management system, their operations were keenly examined
through various methods. This was necessary to find their lacking and the
possible areas to be computerized. Systems approach methodology was used
to develop the system and process, data, and behavioral modeling was used
to design the system. And they were crosschecked to avoid any
inconsistency and lack of integrity. The system had to be a general one to fit
in any. Finally, the physical creation of the system was started according to
the design specifications and tested after completion. User-friendly
interfaces were created that can be used with basic computing skills. Direct
user involvement was there to fulfill their requirements and evaluate its
achievement as well as to find faults if any is there. The system development
life cycle has been described along with some screen outputs in the report to
have a rich and clear understanding of the system.

 Computers are used in almost every field and profession to perform to
perform a large number of useful activities. Technological innovation over
the last two decided have not only increases the range of technically feasible
applications they have also reduced costs so that computer provide a cost
effective solution to far wider range of problem than computer provide a
cost effective solution to a far wide range of problem than they did before. In
business, bank to transfer funds electrically from one location to another use
computers. Computers are used to control inventory, and computerized
robots are used to wield parts together, paint and much more. With office
automation the computer is used for word processing, electronic mail, voice
storage and forwarding, facsimile and teleconferencing. In science and
engineering, computers are unlocking the secrets of our universe. In business
organization, computer easy maintain accounting system and payrole. In
health care, computers are used to keep people in shape. In the military
computers are used to help people locating oil and diagnosis of medical

Today software is the rapid growing tool for solving complex ideas. In our
country most of the business center do not use software. But using software,
a shopping mall can maintain its all kinds of daily, monthly, yearly accounts
and can produce an invoice.

There is another major area computer application is not so matured as they
that is in inventory system. Form the ancient time; inventories are playing a
vital role in customer and product information.

Inventory and control system has been designed to aid small-scale business
organization for maintaining their day-to-day sales activities. The
organization can make it.

Invoice through this software and can produce daily, monthly or yearly
reports and a particular any one invoice and also provide hard copy for
The object of the inventory and control system is to maintain sales and
monitoring environment. This current work is to design a computerized
computer farm’s sales system.
The existing system can handle product’s information, employee’s
information and customer’s information. This system managed all sales
processing of computer’s farm. By this system customer can easy to handle,
easy to get particular employee information, customer information
according to employee id and client id. We can find out how many
particular product are present in product table and also know if the
particular current product are less than ten by the help of alert massage of
product form’s quantity field. Also we have a discount option. If we want to
discount the total amount then we have a amount then we can entry the
amount of discount rate at discrete field and show the amount of the
discount at the discount amount field. In order form we have a search option
according to invoice, no which can help us to find out. Which date the
invoice is created. Every form has necessary button, which can help us new
record add, execute query. Clear the form, first record of the database,
previous record, next record and last record of the database, of delete the
particular form database by the help of alert massage, save the record and
exit the form by also help the alert massage. In a word the overall system is
user friendly.

Although there are again some different of opinion about constitute a
database system, the most prevalent view is that such are designed around a
signal integrated information file or data link.
This file is located directly accessible on time storage. Transactions are
introduced into system only once; all database records that these
transactions affect are update at this time of input. The total file may be sub-
division into application. The database concept throughout the business.
And this requirement, in turn, calls for rigid input discipline; it also measure
the some one in the organization must be given the overall authority to
standardized that these (and provide any necessary change to) data with
company-wide usefulness, such as part number and customer and employee
identification codes, in order to ensure that inconsistencies in data not
introduced into the system.

One reason for the interest in database system is that a database system,
combined with data management software that will organize, process, and
present the necessary elements, will enable managers to search, probe and
query file contents in order to extract answer to nonrecurring and unplanned
question that are not available in regular reports. These question might
initially be vague and\or poorly defined, but the manager can browse
through the database unit he has needed information. In assemble the
needed items from a common database in response to the queries of a
manager who is not a programming specialist. In the past manager used to
prepare such reports using a database through a programmer at the cost of
time and patience.

In addition to having direct access to data generated within the organization,
a manager may also have externally produce information at finger trips in
the database.
The concept of database:

Informally a database is refereed to a collection of mutually related data, to
the computer hardware that is to store it, and to the programs that are used
to store it, and to the programs that are used to manipulate it. In this section,
the concept of a file will be defined, since files are the prime component of
database concepts.
Then operations or tasks, performed when using a database, will be


A database is a collection of related data. The data storage for a database is
accomplished by the use of one or more files. A file is defined to be
collection of similar records kept on secondary computer storage devices.
Typical secondary
storage device us dusk drives with magnetic disks, although a number of
alternate possibilities are there. A record is defined to be a collection of
related fields containing elemental data items. A data item typically
represents a value, which is part of a description of an object or an event.
Computational process can manipulate such values.

Computation on a database:

In the foregoing section some of the static aspects of a database are
considered, namely, the storage of data as files, records and fields. Now let
us look at a database from a dynamic point of view. The study of dynamic
behaviors of programming structures is the presswork whenever operating
system has to be analyzed. The term computation is used to denote a section
of an application that manipulates the database. Most of the computations,
which are used to manipulate data collections, are conceptually simple. Four
types of computations related to database.
1.Bulding of the data collection:
The updating of a database includes data collection, data organization, and
data storage. This aspect is often the most costly part of a database

2.Updating of data elements in the data collection:
The updating of a database includes the additional of new data, change of
data values when necessary, and deletion of invalidated or obsolete

3.Retrieval of data from the data collection:
Data retrieval can consists of the fetching of a specific element in order to
obtain a stored value or fact, or the collection of related elements to obtain
data regarding some collection of sets of related elements to obtain data
regarding some relationship, which describes itself when data are joined.

4.Reduction of large quantities of data to useable form:
When the desired information is diffused throughout the database, it may be
necessary to access most of its contents and summarize or abstract the data.
So that the volume presented is manageable and useable form, statistical
summarizes, annual business operating statements, or graphical data
presentations are examples have frequently used data-reduction techniques.

Applications are that employ database systems currently include
1.Manufacturing with inventory management, bills-of-materials processing,
and production-equipment scheduling.
2.Service industries with lists of capabilities an allocation schedules.
3.Economical models with production and consumption data for allocation
4.Financial institutions with lists of individual accounts, assets, and
convertibility of funds.
5.Scientific research with collection of previously gathered data used to
determined future research directions.
patient records, database histories, problem classification, and treatment-
effectiveness data.
6.Medical services with patient records, database histories, problem
classification, and treatment-effectiveness data.
7.Descriptive data on individual and property.
8.Libraries cataloging abstract and index of their holdings.

The evolution of database management system:
Business and business management is one of the major parts of the history
of human civilization. Inventory system is one of the major parts of the
history of management information systems. Inventories perform their
schedule works in a traditional way for more than several hundred years.
Today those tools and techniques used in these systems and the prospective
has been developed to a new horizon with advanced of time, skill, and

Difficulty with traditional information system

Traditional information systems have often been found wanting because they
do not provide information with the desirable properties. More specifically,
traditional system often fails in following respects:

1.Information is not timely
Information arrives too late to be of value in planning and decisions.

2.Information is not properly integrated
Potential users may be unaware of the availability of valuable information
produced by the internal departments and external sources. The information
presented to manager is thus complete as it could be.

3.Information lakes conciseness
Too much detail obscure clarity and prevents managers from focusing
attention on those areas of significance that deviate from planned

4.Information is not available in the proper format
Information that arrives is in different format than actually could be of value
for better decision making.

5.Information costs too much to produce
This is especially true when then the information is infrequently and at
different times. Optimum use has often not been made of personal and
available data processing equipment.

6.Information produce is not relevant

Information that produces is of no use because manager is not in a position
to take action that will influence the event repotted. To reduce the
difficulties with tradition approaches, new computer-oriented management
Information System concepts have been developed (and are now emerging).

Management information System:
Management is usually defined as the process of achieving organizational
objectives through the effort of other people. Three important points of this
definition may be emphasized. The first point is that management is the
process, which, when satisfactorily performed, lead to achievement of goals.
The second point is that without the establishment of specific objectives, the
effective practice of management is most difficult, if not impossible. The
third points are that the successful practice of management involves people
working together in harmony to achieve desired result. The availability of
quantity information is operation the term, Management Information
System(MIS) is in dozen of different ways and the definition very in scope
and breadth. MIS’s are networks of computer-based data processing
procedures Developed in the organization as necessary for the people of the
providing manager with and affective information. A procedure is a related
group of data processing stapes or methods, which have been established to
perform a recurring processing operation.

Database management system has evolved from a specialized to central
component of a modern computing environment. As such, knowledge about
database system has become an essential part of an education in computer

A database management system (DBMS) consists of collection of inter
related data and a set of programs to access those data. The collection of
data, usually referred to as a database, contains information about any
particular enterprise.
System development life cycle also referred to as a system study. The
system analyst gives a system development project meaning and direction. A
candidate system is approached after analyst has a through understanding of
user need and problems, has developed a viable solution to these problems
and then communicates the solution through the boundaries of users in the
organization. For example, an inventory and control system may involve
users in the sales and order department, the credit department, the
warehouse, and the accounting department. To make sure that all users’
needs are met, a project team that represents each user works with the
analyst to carry out a system development project. In complex projects,
representatives from other user areas influenced by the candidate system as
well as information systems specialists may also be included.

To understand a system development, we need to recognize that a candidate
system has a life cycle, just like a living system or a new product. System
analysis and design are keyed to the system life cycle. The analyst must
progress from one stage to another methodically answering key questions
and achieving result in each stage.

It is always wise to look ahead, but it is difficult to look further then you can
Winston Churchill’s remark point out that planning future endeavors,
through difficult, is important in operation. System development is not
acceptation. Identifying the need for a new information system and lunching
an investigation and a feasibility study must be on a MIS muster plane that
has management support. Planning cuts across all phases of system life
cycle. It is the first step in developing and managing systems.

System analysis is divided into five phases those are follows:
   1. System planning and the Initial Investigation,
   2. Information Gathering,
   3. The Tools Of Structured Analysis.
   The tools in structure analysis include the following:
         a) Data flow diagram
         b) Data dictionary
         c) Structured English
         d) Decision trees
         e) Decision tables.
   4. Feasibility Study,
   5. Cost/Benefit Analysis.

System design is a solution, a “how to ” approach to the creation of a new
system. This important phase is composed of several steps. It provides the
understanding and procedural details necessary for implementing the system
recommended the feasibility study. Emphasis is on translating the
performance requirements into design specifications. Design through logical
and physical stages of development.

System design is divided into three phases those are as below:
   1. The Process and Stage of System Design
   2. Input/Output and Forms Design
   3. File Organization and Database Design

   No system design is ever perfect. Communication problems,
   programmers’ negligence, or time constraints create errors that must be
   eliminated before the system is ready for user acceptance testing. A
   system is tested for online response, volume of transaction, stress,
   recovery from failure, and usability. Then comes system testing, which
   verifies that the whole set of programs hangs together.

   System implementation is divided into five phases those are as below:
   1. System Testing and Quality Assurance
   2. Implementation and Software Maintenances
   3. Hardware/Software Selection and the computer Contract
   4. Project Scheduling and Software
   5. Security, Disaster /Recovery, and Ethics in System Development.
Designing databases

In Visual Basic & MS SQL server, you use database to organize and relate
tables and views. Databases provide the architecture for storing your data
and have additional benefits as well. When you use a database, you can
create table-level extensions such as field and record-level rules, default
field values, and triggers. You can also create stored procedures and
persistent table relationships. You can use your database to access
connections to remote data sources and to create views of local and tables.

This chapter provides guidelines for planning the tables that go into a VB &
MS SQL server database. It walks you through the database design of the
Imagination traders sample database and provides you with additional
sample database designs.

This chapter discusses:
*Using a Database Design Process
*Analyzing Data Requirements
*Grouping Requirements into tables
*Determining the Fields you Need
*Identifying Relationships
*Refining The Design
*Sample Database Diagrams
Using a Database Design Process:
If you use an established database design process, you can quickly and
effectively create a well-designed database that provides you with
convenient access to the information you want. With a solid design, you’ll
spend less time constructing the database and you’ll end up with faster, more
accurate results.
Note: The terms “database” and ”table” are not synonymous in MS SQL
server. The term database refers to a relational database that is a container of
information about one or more tables or views.
 The key to effective database design lies in understanding exactly what
 information you want to store and the way a relational database
 management system, such as MS SQL server, stores data. To efficiently and
 accurately provide you with information, MS SQL server needs to have the
 facts about different subjects organization into separate tables. For example,
 you might have one table that stores fact only about employee and another
 that stores fact only about sales.

When you organize your data appropriately, you design flexibility you’re
your database and gain the capability to combine and present facts in
different ways. For example, you can reports that combine facts about
employees and facts about sales.

Separating facts into tables adds flexibility to your database.
 When you design database, you first break down the information you want
to keep as separate subjects, and then you tell MS SQL server how the
subjects are related to each other so that MS SQL server can bring the right
information in separate tables, you make it easier to organize and maintain
your data, as well as to build a high-performance application.

Here are the steps in the database design process. Each step is discussed in
later detail in the remaining sections of this chapter.
1.Determine the purpose of your database
knowing the purpose will help you decide which facts you want MS SQL
server to store.

2.Determine the tables you need
 When you have a clear purpose for your database, you can divided your
information into separate subjects, such as “Employees” or “Orders”.
Each subjects will be a table in your database.
3.Determain the fields you need
Decide what information you want to keep in each table. Each category of
information in a table is called a fixed and displayed as a column when you
brows the table. For example, one field in an Employee table could be emp-
name; another could be emp-join-data.4
4.Determain the relationships
Look at each table and decide how the data in one table is related to the data
in other tables. Add fields to tables or create new tables to clarify the
relationship, as necessary.
5.Refine your design
Analyze your design for errors. Create the tables and a few records of
sample data. See if you can get the result you want from your tables. Make
adjustments to the design as needed.
Don’t worry if you make mistake or leave things out of your initial design.
Think of it as a rough draft that you can refine later. Experiment with
sample data and prototypes of your forms and reports. With MS SQL server
, it is easy to change the design of your ,database as you are creating it.
However, it becomes much more difficult to make change to tables after
they are filled with data and after you are built forms and reports. For this
reason, make sure that you have a solid design before you proceed too far
into building your application.

Analyzing Data Requirements

Your first step in designing a MS SQL server database is to analyze your
data requirements by determining the purpose of the database and how it is
to be used. This tells you what information you want from the database.
From that, you can determine what subject (the fields in the tables).

Talk to the people who will use the database. Brainstorm about the
questions you’d like the database to answer. Sketch out the reports you’d
like it to produce. Gather the forms you currently use to record your data.
You’ll use all this information in the remaining steps of the design process.

Example: Tracking Sales and Inventory
Start by writing down a list of questions the database should be able to
answer. How many sales of our featured product did we make month?
Where do our best customers live? Who’s the supplier for our best-selling

Next, gather all the forms and reports that contain information the database
should be able to produce. The company currently uses a printed report to
keep track of products being ordered and an order form to take new orders.
The following illustration shows these two documents.

Forms and reports show some data requirements for your database.

Imagination Traders also needs to paint mailing tables for customer,
employees, and supplies.

After gathering this information, you are ready for next step.
Grouping Requirements into Tables
Determining the tables in your database can be the thickest step in the
database design process. That’s because the results you want from your
database- the reports you want to point, the forms you want to use, and the
questions you want answered---don’t necessary provide clues about the
structure of the tables that produce them. They tell you what you want to
know but not how to categories the information’s into tables.

See the preceding order form as an example. It includes facts about the
customer—the customer’s address and phone number—along with facts
about the order. This form provides you with a number of facts that you
know you want to store in your database. Although the facts are all on the
same form, you can easily prevent common data integrity problems by
storing them in separate tables.

Storing information once reduces change of error. For example, if you only
use one table to store the information for an order form, suppose that one
customer places three different orders. You could add the customer’s address
and phone number to your database three times, once for each order. But this
multiplies the change of data entry errors.

The customer table stores address information once.
Also, if the customer moves, you’d have to either accept contradictory
information or find and change each of that customer’s sales records in the
table. It’s much better to create a customer table that stores the customer’s
address in your database once. Then, if you need to change the data, you
change it only once.

Preventing deletion of valuable information suppose a new customer places
an order and then cancels. When you delete the order from the table
containing information on both customers and their orders, you would delete
the customer’s name and address as well. But you want to keep this new
customer in your database so you can send the customer your next catalog.
Again, it’s better to put the information about order without deleting
customer information.

Look at the information you want to get out of tour database and divide it
into fundamental subjects you want to track, such as customers, employees,
products you sell, services you provide, and so on. Each of these subjects is
a candidate for a separate table.

Tip one strategy for dividing information into look at individual facts and
determine what each fact is actually about.

Determining the Fields You Need
To determine the fields in a table, decide what you need to know about the
people, things, or events recorded in the table, you can think of fields as
attributes, for example, an address field in a customer table contains
customers’ addresses. Each record in the table contains customer, and the
address field contains the address for that customer.

Identifying Fields

Here are a few tips for determining your fields:

Relate each field directly to the subject of the table. A field that describes the
subject of a different table belongs in that other table. Later, when you
define relationships between your tables, you’ll see how you can combine
the data from fields in multiple tables. For now, make sure that each field in
a table directly describes the subject of the table. If you find yourself
repeating the same information in several tables.

Don’t include derived or calculated data

In most cases, you don’t want to store the result of calculations in tables.
Instead, you can have VB &MS SQL server perform the calculations
When you want to see the result. For example, the order form shown earlier
in this chapter displays the extended price for each line of the order in the
Imagination Traders database.

Include all the information you need it’s easy to overlook important
information. Return to the information you gathered in the first step of the
design process. Look at your paper forms and reports to make sure all the
information you have required in the past is included in your MS SQL server
tables or can be derived from them. Think of the questions you will ask VB
&MS SQL server. Can VB &MS SQL server find all the answers using the
information in your tables? Have you identified fields that will store unique
data, such as the customer ID? Which tables include information that you’ll
combine into one report or form? For more information on identifying key
fields and relating tables, see the sections using Primary Key Fields and
Identifying Relationships later in this chapter.

Store information in its smallest logical parts

You might be tempted to have a single field for full names, or for product
names, along with product descriptions. If you combine more than one kind
of information a field, it’s difficult to retrieve individual facts later. Try to
break down information into logical parts; for example, create separate fields
for first and last name, or for product name, category, and description.
Report for tracking the inventory of products
The report indicates that the Product table, which contains facts about
products sold, need to include fields for the product name, units in stock, and
units on order, among others.

Using Primary Key Fields:

The power in a database management system such as MS SQL server comes
from its ability to quickly find and together information stored in separate
tables. In order for MS SQL server to work most efficiently, each table in
your database should include a field or a set of fields that uniquely identifies
each individual record stored in the table. This is often a unique
identification number, such as an employee ID number or a serial number. In
database terminology, this information is called the primary key of the table.
MS SQL server uses primary key fields to quickly associate data from
multiple tables and bring the data together for you.

If you already have a unique identifier for a table, such as a set of product
numbers you’ve developed to identify the items on you can use that
identifier as the table’s primary key. But make sure the values in this field
will always be different for each record – MS SQL server does not allow
duplicate values in a primary key field. For example, don’t u se someone’s
name as a primary key, because names aren’t unique. You could easily have
two people with the same table.

When choosing primary key fields, keep these points in mind:

     MS SQL server doesn’t allow duplicate or null values in a primary
key field. For this reason, you shouldn’t choose a primary key that could
contain such values.

      You can use the value in the primary key field to loop up records, so it
shouldn’t be too long to remember or type. You might want it to have a
certain number of letters or digits, or be within a certain range of values.
     The size of the primary key affects the speed of operations in your
database. When you create primary key fields, use the smallest size that will
accommodate the values you need to store in the field.

Example: Setting the primary Key for the Products table

The primary key of the Imagination Traders Products table contains product
ID number. Because each product number identifies a different product, you
don’t want two products with the same number.

The primary key for the product table is the product-id field. In some case,
you might want to use two or more fields that together provide the primary
key of a table. For example, the product table in the Imagination traders uses
two fields as its primary key: product-id. In the next step, you’ll see why.

Identifying Relationships

Now that you’ve divided your information into tables, you need a way to tell
MS SQL server & Visual Basic 6.0 how to bring it back together again in
meaning full ways. For example, the following form includes information
from several tables.

The order Entry form uses information from several tables.

VB is a relational database management system. That means you store
related data in separate tables. Then you define relationships between the
tables and MS SQL server uses the relationships to find associated
information stored in your database.

For example, suppose that you want to phone an employee with questions
about a sale the employee made. Employee phone numbers are recorded in
the employee table; sales are recorded in the MS-SQL table. When you tell
MS-SQL & Visual Basic which sale you are interested in MS-SQL & Visual
Basic can look up the phone number based on the relationship between the
two tables. It works because Employee-id, the primary key for the employee
table, is also a field in the MS-SQL table is called a foreign key, because it
refers to a primary key from a different, or foreign, table.
So, to set up a relationship between two tables –Table A and Table B- you
add one table’s primary key to the other table. so that it appears in both
tables. But how do you decide which table’s primary key to use? To set up
the relationship correctly, you must first determine the nature of the
relationship. There are three types of relationships between tables:

. One-to-many relationships
. Many-to-many relationships
. One-to-one relationships
Creating a one-to-many relationships:

A one-to-many relationship is the most common type of relationship in a
relational database. In a one-to-many relationship, a record in Table A can
have more than one matching record in Table B, but a record in Table B has,
at mast, one matching record in Table A.

Creating a Many-to-many relationships:

In a many-to-many relationship, a record in table A can have more than one
matching record in table B, and a record in table B can have more than one
matching record in table A. this type of relationship requires changes in your
database design before you can correctly specify the relationship to Visual

Creating a one-to-one relationships:

In a one-to-one relationship, a record in table A can have no more than one
matching record in table B, and a record in table B can have no more than
one matching record in table A. this type of relationship is unusual and
might call for some changes in your database design.
One-to-one relationships between tables are unusual because in many cases,
the information in the two tables can simply be combined into one table.

Refining the design:

When you have the tables, fields, and relationships you need, it’s time to
study the design and detect any flaws that might remain.
You might encounter several pitfalls while you are designing your database.
These common problems can cause your data to be harder to use and

.  Do you have field with a large number of fields that don’t all relate to the
same subject? For example, one table might contain fields pertaining to your
customers as well as fields that contain sales information. Try to make sure
each table contains data about only one subject.
.    Do you have fields that are intentionally left blank in many records
because they aren’t applicable to those records? This usually means that the
fields belong in another table.

.    Do you have a large number of tables, many of which contain the same
fields? For example, you have separate tables for January sales and February
sales, or for local customers and remote customers, in which you store the
same type of information. Try consolidating all the information pertaining to
a single subject in one table. You might also need to add an extra field, for
example, to identify the sales date.

Create your tables, specify relationships between the tables, and enter a few
records of data in each table, see if you can se the database to get the
answers you want. Create rough drafts of your forms and reports and see if
they show the data you expect. Look for unnecessary duplications of data
and eliminate them.

As you try out your initial database, you will probably discover room for
improvement. Here are a few things to check for :

.    Did you forget any fields? Is there information that you need that isn’t
included? If so, does it belong in the existing tables? If it’s information
about something else, you might need to create another table.
.    Did you choose a good primary key for each table? If you use it to
search for specific records, is it easy to remember and type? Make sure that
you won’t need to enter a value in a primary key field that duplicates
another value in the field.

.   Are you repeatedly entering duplicate information in one of your tables?
If so, you probably need to divide the table into two tables with a one-to-
many relationship.

.    Do you have tables with many fields, a limited number of records, and
many empty fields in individual records? If so, think about redesigning the
table so it has fewer fields and more records.

As you identify the changes you want to make, you can alter your tables and
fields to reflect the improved design. For information about modifying
tables, working with tables.

Refining the products table:

Each product in the Tasmanian Traders stock falls under a general category,
such as Beverages, Condiments, or Seafood. The Products table could
include a field that shows the category of each product.

Suppose that in examining and refining the database, Imagination Traders
decides to store a description of the category along with its name. If you add
a Category Description field to the Products table, you have to repeat each
category description for each product that falls under the category – not a
good solution.

A better solution is to make Category a mew subject for the database to
track, with its own table and its own primary key. Then you can add the
primary key from the Category table to the Products table as a foreign key.

The Category table provides a place to store category information
The Category and products tables have a one-to-many relationship: one
category can have more than one product in it, but any individual product
can belong to only one category.

Sample Database Diagrams:

The database diagrams in this section might give you ideas for designing
your own database. These databases aren’t included with Visual Basic;
they’re included here as examples of the types of databases and tables you
can create.

Appointments Database:

This database structure stores appointments for a professional office, and
could easily be modified for use in an office of doctors, dentists, lawyers, or
accountants. The appointments table has a multiple-field primary key to
uniquely identify each appointment. This primary key, the “client_sta”
index, is created by indexing in an expression that combines the client_id
and date_start time fields.

Personnel Database:

This database structure stores human resources information. The Job History
table stores information on each hire or promotion, so it can contain many
records for each employee.

Before designing a system, it should have clear conception about the design
face for achieving this goal.

A person should have the knowledge about system planning and design. For
designing an ideal and effective system we should flow the step, which is
depicted by the following figure.
Information resource:

To develop our software we have collect many information from various
organizations there are Arrange, one-step mall, pride and stop & shop. We
have divided the information resource into two phases one is the interview
and other is the question.

The interview: Interviewing is the most significant and productive fact
finding technique available to the system analyst. Interview is a face to face
interpersonal role situation in which a person called the interviewer asks a
person being interviewed questions designed to gather information about
problem areas.

Here may e creating an opportunity for flexibility in eliciting information
because the person (interviewer) and the person in interviewed meet face to

The questionnaire: The questionnaire is another tool, which can be used at
various times by the system analyst in the system development process.
When the analyst decides to make use of questionnaire there are a few, but
important guidelines to follows:

   1.    Explain the purpose, use, security and disposition of the responses.
   2.    Provide detaile4d instructions on how you want the questions
   3.    Give a time limited or a deadline for return of the questionnaire.
   4.    It is economical and requires less skill to administer than interview.
   5.    The questionnaire places less pressure on subjects for intermediate
   6.    Identify each questionnaire by respondent’s name, job title,
         department etc.
   7.    Include a section where respondents can state their opinions and
The Inventory Problem:

The inventory problem is one of the most typical semi-additive measure
problems. The inventory represents a whole class of semi-additive measure
problems that share a common attribute: keeping track of data snapshots.
Snapshots are typical in applications in which balances are involved, such as
account balances, stock tickers, head count tracking, contact management,
and active insurance policies management. Data snapshots (as opposed to
pure transactions) disable the ability to aggregate data over time correctly.
Although this article refers to the inventory problem, remember that the
applicability of the proposed techniques is broad and can be adapted without
change to wide variety of business problems.

Inventory Example:

The inventory cube has this structure:
  1. Dimensions.
  2. Products: All Products, Family, Category, Name.
  3. Computer Firm: All, Computes.
  4. Time: Year, Quarter, Month, Week.
  5. Measures:
  6. Quantity (SUM)
  7. Value (SUM)

   As explained earlier, summing the quantities and values over the time
   dimension yields incorrect results. These are the items that must be

         . The average quantities and stock values in each time period.
         . The opening and closing balances for each time period.
         . The change in inventory levels between consecutive periods and.
   parallel periods.
         . The minimum and maximum inventory levels in a time period.
           . The relative contribution of the stocked item to the overall stock

End users should not see any data generated by summing over the time

Table Name : Category

Table Name: User
Table Name: Department

Table Name: Wise Product
Table Name: Payment

Table Name: Supplier
Table Name: Measurement Unit

Table Name: Product

Table Name: Purchase Master
Table Name: Purchase

Table Name: Request Detail

Table Name : Request Master
Programming in Visual Basic

In Visual Basic, we use variables to temporarily store values during the
execution of an application. A variable can be thought of as a placeholder in
memory for an unknown value.

For example, imagine we are creating a program to track the sales of PCs.
We do not know the price of a PC or the quantity socked until the sale
actually occurs.

We can use two variables to hold the unknown values that is, PCPrice and
PCSold. Each time the program is run, the user supplies the values for the
two variables. To calculate the total sales and display it in a Textbox named
txtSales, our code would be :

TxtSales. Txt = PCPrice * PCSold

The expression returns a different total each time, depending on what values
the user provides. Variables allow us to make a calculation without having to
know in advance what the actual inputs are.

Variable names in Visual Basic can be up to 255 characters long and
provided the first character is a letter followed by any number of letters
numbers and underscores. The following list shows some variable names
and indicates whether they are valid or not:

        Area 1_square                Acceptable
        1Area_square`                Not acceptable First
                                            character is not a letter
        Area.1                             Not acceptable uses a
        Area&1                       Not acceptable uses &
                                            inside the name
        Area Rectangle Square       Acceptable 19
                                            characters long

Understanding Access- Visual Basic as a Client/Server Combination
Visual Basic is the most commonly used visual programming environment.
It allows us to create front-end applications.

Microsoft Access is an RDBMS used to create client/server applications for
small to medium size enterprises. It is used most popularly with Visual Basic
as the front-end.

Data access in Visual Basic gives us tools to create and use structured
database systems to manage our application’s data. One of these tools is the
data control.

The ability to create and access a database such as Microsoft Access gives us
many programming advantages:

>     It lets us write programs that use existing databases.

>     It allows our application to share data with other programs.

>      It simplifies our programming, since we do not need to handle low-
level file accessing and searching.

Data access in Visual Basic consists of performing operation on a physical
database. We can display the results of these operations and accept input
from to user on Visual Basic forms, using controls.

This approach simplifies the code we need to write and insulates us from the
underlying structure and mechanics of retrieving and updating data.

Advantage of Visual Programming:
>Visual development of graphical user interfaces which are easy to use and
easy to learn.

>A programmer need not write code to display the required component.
>For example, the visual programming environment displays a list of
available components. The programmer picks up the required component
from this list to display it.

>The component can be moved, resized and even deleted, if so required.

>There is no restriction on the number of controls that can be placed on a

>The programmer can create the user interface visually, he can align move
or size the components as required without
having to resort to writing code.

> The interface components provided by the visual programming
environment have some code built into them.

> For example, a button ‘knows’ when it has been clicked upon. In the case
of conventional programming tools, the programmer has to write code to
determine the component that has been clicked and then execute the
appropriate code.

Data type names

Variables are placeholders used to store values; they have names and data
types. The data type of a variable determines how the bits representing those
values are stored in the computer’s memory. When a variable is declared, we
can also assign a data type for it. All variables have a data type that
determines what kind of data they can store.

By default, if we don’t assign a data type, the variable is given the Variant
data type.

If we assign a data type to a variable, Visual Basic can handle that data more
efficiently. For example, a variable to store a person’s age is best
represented as a numeric data type.

The following is the list of data types supported by Visual Basic.

>     Numeric data types
            Integer
            Long Integer
            Single
            Decimal
            Double
            Currency

>     Byte data type
>     String data type
>     Boolean data type
>     Date data type
>     Object data type
>     Variant data type
>     User-defined data type

Declaring Variables

To declare a variable is to tell the program about it in advance. We declare a
variable with the Dim statement, supplying a name for the variable:

Dim variable name ( As type)

The Dim statement is the short form of dimension.

The optional ( As type) clause in the Dim statement allows us to define the
data type of the variable we are declaring. Data types of information the
variable stores.

For example, to declare a variable num1 as an integer the declaration in
Visual basic would be as follows:

Dim numl As Integer
Some points about Global and Local Variables:

>     Memory for the variables is allocated when the declaration for the
variable is encountered.

>      Global variables are declared just before the code for the program
starts. Thus, memory for global variables is allocated just before the
execution of the program begins. This memory stays allocated till the
program terminates.

>     Memory for the local variables is allocated at the start of the
procedure when the declarations are encountered and the memory is freed
when the end of the procedure is reached.

>   It is better to use local variables than global variables because
memory is used only as and when required by the local variables.

Key Concept:       Key is a minimal set of attribute or attributes that identify
a now which distinguish entities from each other. Key must be needed to
easy access database:

      (a) To for relation among altitudes in a relation or a group of

      (b)    To identify a tuple uniquely.

Function of Key:

      (1)    Super Key
      (2)    Candidate Key
      (3)    Primary Key
      (4)    Foreign Key
Super Key: The combination of the attributes able to select specific row in
the relation uniquely is called a super key.
Candidate Key: A candidate key is that attribute in the relation which
must be able to select a row or record uniquely without help of other. To do
00 candidate key must satisfy two conditions

      (1)   The value of that attribute can never be of null.
      (2)   That attribute never accepted duplicate value.

Primary Key:      An attribute able to select a row in the relation uniquely
and nominated by the DBA as key of that relation is primary key.

Foreign Key:        The primary key of a relation exist is other relation to
represent its parent tubule is called a foreign key.


Simple applications can consist of just a single form, and all of the code in
the application resides in that form module. As the applications and more
sophisticated, we may need additional forms and there are chances that
certain code gets repeated in several forms.

To avoid such duplication of the code, we create a separate module
containing a procedure that implements the common code. Visual Basic
provides three modules:

From modules: -Associated with each form is a related form module, which
contains its code. For each control placed on the form the form module
contains a corresponding set of procedures, which are executed in response
to an event. From modules have a filename extension (.FRM).

Standard modules: Code that is not related to a specific form or control is
placed in a different type of module, called the standard module (.BAS).
Procedures that are to be used repeatedly in response to events in several
different controls are placed in the standard module. This avoids duplication
of the code.

Class modules:- A class module (.CLS) is used to create controls that can be
called from procedures within the application, A standard module contains
only code whereas, a class module contains both code and data that is, we
can think of it as a control without a physical representation.
     1. Fundamentals of Database System by Elmasri & Navathe.
     2. UML Crash Course by Thomas A Pender.
     3. Software Engineering by Roger S. Pressman.
     4. Sql, Pl/Sql by Ivan Bayross.
     5. Teach yourself Visual Basic in 21 Days – Sams.
     6. Visual Basic 6.0 by Gary Cornell

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