smitha

Monday, May 01, 2006

Distinguih between IRS and DBMS

Information retrieval system:
The term information retrieval was coined in 1952 and gained popularity from 1961 onwards. At that time information retrieval’s function was seen as a major advance in libraries that were no longer just storehouses of books, but also places where the information was catalogued and indexed.

Definition:
According to Harter information retrieval system "is a device interposed between a potential user of information and information collection itself for a given information problem, the purpose of the system is to capture wanted items and to filterout unwanted items".
The concept of information retrieval system is to some extent self explanatory from the terminological point of view. One may simple denote such a system as one that stores and retrieves information.
The three major areas that constitute an information retrieval system are:
1. Items of information
2. Users queries and
3. Matching of these queries with the document database.

DataBase Management System:
A database management system is a collection of programms that enable you to store, modify and extract information from a database. there are different types of DBMS, ranging from small systems that run on personal computers to huge systems that run on mainframes.A database management system is a computer program designed to manage a database and run operations on the data requested by numerous clients. DBMSs have more recently emerged as a fairly standard part of any company back office.DBMSs are found at the heart of most database application sometimes DBMSs are built around on private multitasking kernel with built-in-networking support although nowadays these functions are left to the operating system.

A database application is computer software written to manage the data of a particular application or problem.In database management system, data can be retrieved in three levels.
1. Physical level
2. Conceptual level
3. User level

Distinguish between IRS and DBMS:


1. One of the most distinguish features of DBMSs is that they offer an advanceDataModellingFacility(DMF) including DataDefinitonLanguage and DataManipulationLanguage for modelling and manipulating data.
IRSs do not offer an advance DMF. Usually datamodelling in irs is restricted to classification of objects.


2. A major strength of the DataDefinitonLanguage of DBMS is the capability to define the data integrity constraints.
In IRSs such validation mechanisms are less developed.


3. DBMSs provides precise semantics.
IRSs most of the time provides imprecise semantics.


4. DBMSs has structured data format.
Wereas, IRSs is characterised by unstructured data format.


5. Query specification is complete in DBMS.
In IRS query specification is incomplete.


6. Query language is artificial in DBMS.
In IRS query language is near to natural language.


In DBMS, one normally looks for an exact match. In IR, more generally one is satisfied with the partial match and then select best one among the selected items. Both IRS and DBMSs are equipped with some basis data management facilities and application development facilities. Often DBMSs are the more advancedin this respects.