Relationship of application program And DBMS

Application Program

                  An application program is a program that is used to send commands to the database management system to manipulate the database. These commands are sent to DBMS through the graphical user interface. The user interacts with an application program. The application program further interacts with a database management system. Two important application programs are Developer2000 and Power Builder.

 

Relationship between DBMS and Application Program

                  A database application is developed by using both the application program and database management system. The application program contains the user interface. The user uses this interface for communication with the database management system to manipulate the database. The application program is also called the front-end and the database is known as the back-end.

                 The relation of application program and database management system is very important. When a database program is developed, a way of communication with the program is required for the user. The user cannot use the database directly. An easy and simple interface is required so that the user can easily use the database.

                  Another important relationship between DBMS and application program is that is used to produce effective and informative for taking a different decision about the business.

User 🔛 User Interface 🔛 Application Program  🔛  DBMS 🔛 Database

 

Range of Database applications

                   The range of database applications is as follows:

1. Personal Computer Database

                   Personal computer databases are specially designed for a single user. The user may be using a stand-alone desktop computer or laptop. The representatives of a medical company may use laptop computers when working in the market. This computer may use a simple database application in which the records of customers are stored. Some important decisions about the development of personal computer database application are as follows:

• It should be purchased or developed within the organization?
• It should be developed by an end-user or a professional in the information system?
• Required data and the design of the database
• Selection of DBMS for database application
• Synchronization of a personal computer database with other databases
• Accuracy of data in a personal computer database

              Personal computer databases are widely used. A problem with this database application is that it is difficult to share quickly. For example, if the head of a medical company wants to get complete information about his customers, it cannot be done quickly as it is stored on the laptop computers of different representatives.

2. Working Database

             A workgroup is a team of people who work on the same project collectively. A workgroup normally consists of less than 25 people. A type of database that is specially designed to support workgroup is known as a workgroup database.

              The people in the workgroup are connected with some through a local area network (LAN). The database is stored on a central computer called a server. All members of the workgroup can share this database.

                   Workgroup database provides many facilities but arises some problems also. The main problem is of security and integrity of data when the data is updated concurrently. Some important decisions about the workgroup database are as follows:

• Database optimization to satisfy the requirements of different members of the workgroup
• Concurrency control

The decision about the location of different operations i.e. on server or workstation  

3. Department database

                     A function unit in an organization is known as a department.  An organization may have marketing, production, and accounting departments. A department normally consists of 25 to 100 people. Department database is specially designed to support are as follows:

• Database design for efficient performance to handle a large number of users and transactions
• Proper security to protect data against unauthorized access
• Database tools for complex environment
• Ensure data redundancy and consistency if data is used in different departments 

The need for the distributed database if users are geographically away from one another

4. Enterprise Database

                    A type of database that is specially designed to support to support the function of a whole organization or many departments of an organization is known as an enterprise database. The most important enterprise database is known as a data warehouse. The contents of a data warehouse are derived from many operational like personal computers, workgroups, and department databases.

                    Suppose a university has many departments like CS, Biology, Agriculture, etc. each department user a department database to maintain the function of the department. The Vice-Chancellor needs to get the information of different departments frequently. In order to satisfy this requirement, a data warehouse can be developed for the whole university in the VC office. The data warehouse will extract the different departments periodically.

                         Some important decisions about department database are as follows:

• Distribution of data among various locations in the corporate structure

Maintenance of standards for data names, definitions, and formats

 

Types of Users

          There are different types of users that play different roles in a database environment. Following is a brief description of these users:

1. Application programmers

              An application program is a professional who writes computer programs in a high-level language. These programs can be used to interact with databases. Application programmer designs application programs according to the requirements of the users. He works according to the specification provided by the system analyst.

2. End Users

           End users are those persons who interact with the application directly. They are responsible to insert, delete and update data in the database. They get information from the system as and when required. Different types of end-users are as follows:

• Naïve User: Naive users are users who have no technical knowledge about the DBMS.  they use databases through application programs using the simple user interface. They perform all operations by using simple commands provided in the user interface the data entry operator in an office is responsible for entering records into the database. He performs this task by using menus and buttons etc. he does not know anything about databases or DBMS. he interacts with databases through an application program.
• Sophisticated Users: Sophisticated users are the user who is familiar with the structure of database and facilities of DBMS. Such users can use a query language such as SQL to perform the required operations on the database. Some sophisticated users can also write application programs.

3. Database Administrator

               The database administrator is the most technical user. He is responsible for managing the whole database system. De designs, created, and maintains the database. He manages the users who can access this database and controls integrity issues. Some important functions of a database administrator are as follows:

• Installation of software
• Monitoring of database system
• Solution of any problem that occurs in the database system
• Assigning permission to different users to the user to the user database system
• Taking regular backups of the database
•  Restoring the system in case of any problem or system crash

History of Database systems

               The concept of a database was introduced in the 1960s. since then, a lot of work has been done in this field. Following is a brief discussion about the history of the database.

1960’s

           In the 1960s, computers became cost-effective for companies, and the storage capacity of computers increased. Two main data models were developed:

1. Network model(CODASYL)
2. Hierarchical(IMS)

           Access to the database was through low-level pointer operations. Storage details depend on the type of data to be stored. Thus adding an extra field to your database requires rewriting the underlying access/modification scheme. Emphasis was on records to be processed, not the overall structure of the system. A user would need to know the physical structure of the database in order to query for information. One major commercial success was the SABRE system from IBMS and American Airlines.

1970-72

E.F Codd proposed a relational model for databases in a landmark paper on how to think about databases. He disconnects the schema (logical organization) of a database from the physical storage methods. This system has become standard since then.

1970’s

Two main prototypes for relational systems were developed during 1974-77. These provide a nice example of how theory leads to best practice.

• Ingres: Developed at UCB. This ultimately led to Ingres Corp., Sybase, MS SQL server, Britton-lee, Wang’s PACE. This system used QUEL as query language.
• System R: Developed at IBM San Jose and led to IBM’s SQL/DS & DB2, Oracle, HP’S All base, Tandem’s Non-Stop SQL. This system used SEQUEL as query language.

1976

          p. Chen proposed Entity-Relationship(ER) model for database design. It gave another important insight into the conceptual data model. Such higher-level modeling allows the designer to concentrate on the use of data instead of logical table structure.

Early 1980’s

In the early 1980s, the commercialization of relational systems took place.

Mid 1980’s

                 SQL(Structured Query language) because of a standard. IBM launched DB2. The importance of network and hierarchical models was decreased. The development of the IBM PC gave rise to many DB companies and products such as RIM, RBASE 5000, PARADOX, OS/2 Database Manager, D base III, IV (later fox base and then visual FoxPro), Watcom SQL.

Early 1990’s

               In the early 1990s, much was done on client tools for application development such as PowerBuilder (System), oracle Developer, VB (Microsoft), etc. The client-server model for computing became the norm for future business decisions. The work on Object Database Management Systems (ODBMS) prototypes also started during this period.

Mid 1990’s

                  The usable Internet /WWW appeared in the middle of 1990. It allowed remote access to computer systems. The concept of/Wed/DB started to grow.

 

Late 1990’s

                  Internet companies worked for Web/internet/DB connectors. Examples are Active Server pages, FrontPage, Java Servlets, JDBC, Java Beans, ColdFusion, Dreamweaver, Oracle Developer, etc. The open-source solution came online with population use of etc, Apache, MYSQL, etc. Online Transaction Processing (OLTP) and online analytic processing (OLAP) come of age with many merchants using point-of-sale (POS) Technology on a daily basis.

Early 21st Century

         The growth of DB applications continued in the early 21st century. The more interactive application appeared with the use of PDAs. The main companies that predominated the large DB market are IBM, Microsoft, and Oracle.

Future Trends

            Huge (terabyte) systems are appearing and the handling and analyzing data has become very complex. Large science databases such as genome project, geological, national security, and space exploration data have been developed. Data mining, warehousing, data marts are commonly used techniques today. This trend will continue in the future.

          XML with Java has become a popular technique. The mobile database is now coming to market in various ways. Distributed transaction processing is also becoming very popular for business planning in many areas.

 

 

• Introduction to Databases