Business Support System: Indian School Of Mines Dhanbad

BUSINESS SUPPORT SYSTEM BY: TANMAY KUMAR VIBHOR BHARDWAJ PRABHAKAR KUMAR GARGI MUKHOPADHYAY KUMAR GAUTAM SINGH

INDIAN SCHOOL OF MINES DHANBAD

DATA BASE • A collection of related pieces of data: • Representing/capturing the information about a real-world enterprise or part of an enterprise. • Collected and maintained to serve specific data management needs of the enterprise. • Activities of the enterprise are supported by the database and continually update the database.

An Example: • University Database: – Data about students, faculty, courses, researchlaboratories, course registration/enrollment etc.Reflects the state of affairs of the academic aspects ofthe university.

• Purpose: To keep an accurate track of the academic activities of the university.

Database Management System (DBMS) • A general purpose software system enabling: – Creation of large disk-resident databases. – Posing of data retrieval queries in a standard manner. – Retrieval of query results efficiently. – Concurrent use of the system by a large number of users in a consistent manner. – Guaranteed availability of data irrespective of system failures

DBMS • There are many different types of DBMSs, ranging from small systems that run on personal computers to huge systems that run on mainframes. The following are examples of database applications: – – – –

computerized library systems automated teller machines flight reservation systems computerized parts inventory systems

WHY DBMS? • Designed to manage a large body of information. • Defining structures for storing information and providing mechanisms for manipulating the information. • Provide for the safety of the stored information. • Must avoid possible anomalous results due to multiple users concurrently accessing the same data. Examples: Microsoft Access, MySQL, Microsoft SQL Server, Oracle and FileMaker Pro

OS File System Storage Based Approach • Files of records –used for data storage – data redundancy –wastage of space – maintaining consistency becomes difficult

• Record structures –hard coded into the programs – structure modifications –hard to perform

• Each different data access request (a query) – performed by a separate program – difficult to anticipate all such requests

• Creating the system – requires a lot of effort

• Managing concurrent access and failure recovery are difficult

DBMS Approach • DBMS – separation of data and metadata – flexibility of changing metadata – program-data independence

• Data access language – standardized –SQL – ad-hoc query formulation –easy

• System development – less effort required – concentration on logical level design is enough – components to organize data storage process queries, manage concurrent access, recovery from failures, manage access control are all available

HISTORY • Databases have been in use since the earliest days of electronic computing. • Older systems were tightly linked to the custom databases in order to gain speed at the expense of flexibility. • Originally DBMSs were found only in large organizations with the computer hardware needed to support large data sets. 1960s Navigational DBMS Charles Bachman founded the "Database Task Group" within the group responsible for the creation and standardization  IBM also had their own DBMS system in 1968, known as IMS. 

CODASYL, of COBOL.

1970s Relational DBMS – Edgar Codd worked at IBM was involved in the development of hard disk systems – outlined a new approach to database construction that eventually culminated in the groundbreaking A Relational Model of Data for Large Shared Data Banks.

End 1970s SQL DBMS IBM started working on a prototype system loosely based on Codd's concepts as System R.  started on multi-table systems in which the data could be split so that all of the data for a record did not have to be stored in a single large "chunk“.

COMPONENTS OF DBMS • DBMS Engine: accepts logical request and converts them into physical equivalent, and actually accesses the database and data dictionary. • Data Definition Subsystem: helps user to create and maintain the data dictionary and define the structure. • Data Manipulation Subsystem: helps user to add, change, and delete information in a database and query it for valuable information. • Application Generation Subsystem: contains facilities to help users to develop transactions-intensive applications. It facilitates easy-to-use data entry screens, programming languages, and interfaces. • Data Administration Subsystem helps users to manage the overall database environment

TYPES OF DATABASE 1. Hierarchical  

hierarchical relationships between data i.e. parent - child. advantage of the management and programming aspects of the products.

1. Network data model   –

allowed complex data structures to be built but were inflexible and required careful design. Very efficient in storage and fast however - best examples are airline booking systems. Advantages • Fast • Efficient

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Disadvantages • Inflexible • Technically obsolete (although many in commercial use).

….contd 3. Relational data model use the Structured Query Language (SQL) to extract and update data and conform as closely as possible to the theoretical relational rules of normalization.  Oracle, Sybase, Informix etc are examples Advantages • technical development effort ensures that advances e.g. object orientation, web serving etc appear quickly and reliably. • Extremely well developed management tools and security with automatic data logging and recovery. Disadvantages • employ many tables to conform absolutely to the various normalization rules. This can make them slow and resource hungry compared to more flexible systems.  • SQL does not provide an efficient way to browse alphabetically through an index. Thus some systems cannot provide a simple title A-Z browse. 

FUNCTION OF DBMS • • • • • •

Data Definition Data Manipulation Data Security & Integrity Data Recovery & Concurrency Data Dictionary Maintenance Performance

Advantages of DBMS • • • • •

Redundancy is controlled Unauthorized access is restricted Providing multiple user interface Enforcing integrity constraint Providing backup and recovery.

Uses of DBMS in different sectors • • • • • • • • •

Banking Airlines Universities Credit card transactions Telecommunications Finance Sales Manufacturing Human Resources