Functions Of Database Management System

Functions Of informationbase focusing governing bodyBefore we pay off with selective informationbase management constitution we should hold out what is selective in stageion. A selective information is a piece of in ashesation, and infobase is the prayer of entropy that is set in an orderly way. And managing this entropybase is cognize as database focusing organisation in short database management frame. The person who manages, creates, controls and maintain this database management brass is known as Database Administrator (DBA). An separate(a) important term to retrieve is information. Any data which has been converted to a useful and understandable form is called information. at that key out ar some differences between data and information.Data dataAny raw figure or fact is data.For example 6 is a data.A processed form of data is known as information.For example weight = 6 kg is dataData does non help in qualification decisions.With right information we sti nker hand decision.Functions of Database attention arrangementData puzzleing The structured definition of data storage is known as data modeling. touch Query This a mechanism of manipulating the dataConcurrency Control To ensure the accuracy and simultaneous entranceway of the database by multiple exploiters.Security of Information Security of the database is in truth(prenominal) important. doss down Reco in truth(prenominal) Data reco genuinely after the system crashes.Types of Database usersDatabase Administrator (DBA) The database administrator is the person who who maintains casts and creates the database.Database Designer A database designer is a person who plans or designs the database. nullify User The sensation who uses the database, it may be that he/she besides views the database or it may be that he/she devises the data entries. Make queries, etcThere may be opposite types of end user, for exampleSophisticated these ar the users who has a good acquaintance in database and mass make queries, with SQL keep in line data with DML (Data Manipulating Language)Specialized who makes use designs that interacts with the databaseNative only interacts with the database via some forward-looking programsApplication Programmers A person who makes applications which interacts with the database using programming language want C++ , Java, etc. He may create a computer softw be which gives a easy to use interface to input data into a complex database, so that even the clerks of the office potful input data or look for for some data from the companies database without knowing Oracle, MySQL or other database management system softw atomic number 18Database ModelDatabase Model is the structure or the format of the data it may be physical or conceptual. Database Model is in like manner known as database outline.Conceptual Model Conceptual Model helps to overview the organisational schema sooner than the database schema. sensual Model Physical Mo del is the database design which instrument that this model describes the data storage, data structure, etc. basically we accept to know about the physical media of the data storage and the mode of admittance of that data from this model.Frame Memory Model This type of model is chiefly used for heroic manufacturing database application. Modifying the characteristic of the complex database easily and accurately.Unifying Model in the Unifying Model the Entity-Relation concept has been extended to introduce a new form of diagrammatic representation other than class diagrams. bearing Oriented Model A Object Oriented Model is a data model in which the real life data or entities ar organized. Generally Object Oriented Data Model or OODM consists of the following concepts, they are as followsObject and object identifierAttributes and methods differentiateClass hierarchy and inheritanceRecord ground Model The Record Based Model helps us to specify the overall logical structure of the database. In this type of data bases the images of types of data are fixed. And each of the testify type or data type has a fixed number of fields with fixed field length. There are three types of destroy based data model they areHierarchical Model In a Hierarchical Model the data is organized in a form of tree like structure. In this kind of structure the rise up child relationship can easily be shown. A very famous use of this kind of database is the Windows Registry developed by Microsoft.320px-Hierarchical_Model.jpg net profit Model This is a type of database model where it is easy to represent objects and relationship. Its more(prenominal) easier to define m each to many relation in this model rather than in the hierarchical model. A well known implementation of intercommunicate Model is RDM Server.320px-Network_Model.jpgRelational Model The relational model was developed by E.F Codd. The properties of a relational database model are as followsThe columns of table are a ll homogenous i.e. they are of the very(prenominal) kind. all(prenominal) item should catch simple prise.All the relationship of tuples must be distinct.The key value should be used to order the tuples within a relationship.Columns are named intelligibly and their ordering is not so important.280px-Relational_Model_2.jpgManual Database.A Manual Database is a drop kept by a human without the use of any computers or electronic devices. This obviously has many problems likeSearching It is very difficult to find a particular result from a manual of arms database if the sizing of the database is huge.Updating Updating a new entry is as well as problematic as we have to manually find the old record, slit it, or erase it wherefore make the new entry.Backing up retrieve on that point is a database of 10,000 pages making a manual alleviation of this database, i.e. a handwritten copy of it will be difficult to make. sieve It is virtually unsurmountable to sort the data say names of customers by alphabetic order, etc on a manual database.As we see that making a manual database of a mountainous amount of data becomes im likely to manage so now we use computerized data.Traditional point affect SystemOne of the earliest forms of computerizing data storage is the file away bear on system. Creating, sorting, organizing and glide slopeing the content of the file is known as File impact System.Characteristics of File Processing System.Each file is different from each other.This is a collecting of files, or sorted data.Each of the file is called a flat file.Every file contains processed information of a specific function such(prenominal) as one file may be for accounting other file may be of contacts.Files are created by the help of program which are written in C, C++ or COBOL.Drawbacks of the File Processing System.There are many drawbacks of File Processing System.Separated DataDuplicated DataData DependencyData inflexibilityProblems in representing the da ta to user.File format problems.Database A database is a organized form of data. This establishment is very important because when the size of data increases it becomes difficult to use or control the data.Database steering System A database management system or Database management System is a collection of data and programs which help us to admittance and modify those data. The collection of data is called database. The main purpose of database management system is to expeditiously store and control the database.Advantages of database management systemControl surplusage With the help of DBMS data redundancy can be cont brandished. In the File Processing System there used to be data redundancy, which factor that the kindred data stored more than once.Integrity Maintaining Integrity means that the data stored in the database is accurate and precise. This is very much important as incorrect data can not be stored into the database so some integrity constraints are enabled on th e database, to check the accuracy of the database.Avoiding inconsistency Consider there are two data storage sites of data and some throws are do in one site but those changes are not reflected on the other site for some reasons then it gives rise to data inconsistency. To nullify this data redundancy should be removed if data redundancy is canvas it will also remove data inconsistency.Data Sharing Suppose a same data is required by two databases then that data can be shared from a centralized database.Maintaining standards As we know that DBMS is a centralized system so it can be order effectively. A companion database can be standardized in Department Level, National Level, International Level, etc.Preventing unauthorized nettle Lots of security can be enabled to prevent the unauthorized glide path of the data. Passwords and encryptions are enabled in database to provide better security to companys data.Backup and recovery of data Data outrage can slip by at any moment d ue to number of reasons so it is very much important to create backup so that the data can be recovered if there is any accidental loss of data.Disadvantages of DBMSComplexity The functionality of DBMS is a very complex process. The database designer, database administrator, developer and the end user should have a clear understanding of the DBMS working and functionality to make it work in a correct way. If they fail to do it DBMS will not work in a proper way. coat As age passes the size or the volume of data increases which makes the size of database larger. Moving, copying and editing this large amount of data take a considerable while and system resource. Some eons upgrading RAM or record book Space becomes necessary to run the DBMS properlyPerformance DBMS software tends to run slower than the typical File Processing System. follow Cost of implementing the DBMS is high. Sometimes the DBMS software for the specific environs is high, or the upgradeing of hardware to run it b ecomes costly or when converting from an older system to DBMS the process of conversion of the data costs a lot. ill luck rate higher As it is a centralized system I it fals every operation comes to a halt.Difference between File management System and Database trouble SystemFile Management SystemDatabase Management SystemFile management Systems are relatively small in size and volumeDatabase Management Systems are comparatively larger in size.They are cheaper to implementMuch costlier to implementIt deals with few filesIt deals with a large number of files.The structure of this system is very simpleThe structure is very much complex in nature.There are many otiose data.Redundant data is very much reduced.Data inconsistency takes sharpen in File Management SystemData inconsistency is analyse in the DBMSIn File Management System data is isolated.In DBMS data can be shared.There is no security.It is secured.Very simple and primitive form of backup and recovery.Highly civilize and complex form of backup and recovery.Mainly single user.Most of the time its multiuser.Less preliminary designVast preliminary design manipulation of DBMSDatabase Management System is very useful and is used in many sectors. Some the areas where it is used is given below.Railway for making the railway line enquiry and reservation system to work properly there is a needed of implementing DBMS as all the data has to be stored in a centralized placement and the data is then used by every railway move throughout the country.Banking As now a days there are many branches of a bank there has to be a DBMS to track and record the transactions of every customers. This will have not been possible if File Management System were used.Schools/Colleges and Universities To store the records of students like their name, roll number, address, contact number, marks obtained, etc a DBMS is used so that the database can be updated easily.Business and Offices To store the companys sales, profit , etc a nd its record of employees a in advance(p) DBMS is used.Instances and SchemasThe database changes from time to time, the information which is stored in the database at a particular time is known as Instance. A Schema is a overall design of the database .QUESTIONSWhat do you mean by DBMS?A DBMS or Database Management System is a collection of data and programs which help us to access and modify those data. The collection of data is called database. The main purpose of DBMS is to efficiently store and control the database.How does DBMS differs from MS Excel?What are the differences between data and information?What is the difference between Conceptual Model and Physical Model?Conceptual Model Conceptual Model helps to overview the organizational schema rather than the database schema.Physical Model Physical Model is the database design which means that this model describes the data storage, data structure, etc. basically we get to know about the physical media of the data storage and the mode of access of that data from this model.What are the difference between Traditional File Management System and Database Management System?Traditional File Management SystemDatabase Management SystemFile management Systems are relatively small in size and volumeDatabase Management Systems are comparatively larger in size.They are cheaper to implementMuch costlier to implementIt deals with few filesIt deals with a large number of files.The structure of this system is very simpleThe structure is very much complex in nature.There are many senseless data.Redundant data is very much reduced.Data inconsistency takes place in File Management SystemData inconsistency is suss out in the DBMSIn File Management System data is isolated.In DBMS data can be shared.There is no security.It is secured.Very simple and primitive form of backup and recovery.Highly sophisticated and complex form of backup and recovery.Mainly single user.Most of the time its multiuser.Less preliminary designVas t preliminary designWhat do you mean by Data Duplicity?Data Duplicity means repetition of the same data more than once in the same database. Data Duplicity causes lot of problems likeIt is waste of time and money.It leads to loss of data integrity.It takes up additional storage and increases the size of the database which effects the search time.What do you mean by Data Dependency?In a File Processing System the specific physical format of file and record were hard coded on the application programs. So a change in database format required the codes to be updated.What is data isolation?Data Isolation means a data which is isolated form other databases that means when data can not be shared. It is not possible to share data in a File Processing System so the data remains in a isolated condition. make unnecessary down the necessary steps to secure a data into a database.What do you mean by redundant data?Data Redundancy means duplication of data. A same data may be present more than on ces leading to data inconsistency.Write down the applications of Database Management System.There are many applications of Database Management System , some of them are explained belowRailway for making the railway enquiry and reservation system to work properly there is a needed of implementing DBMS as all the data has to be stored in a centralized location and the data is then used by every railway stations throughout the country.Banking As now a days there are many branches of a bank there has to be a DBMS to track and record the transactions of every customers. This will have not been possible if File Management System were used.Schools/Colleges and Universities To store the records of students like their name, roll number, address, contact number, marks obtained, etc a DBMS is used so that the database can be updated easily.Business and Offices To store the companys sales, profit , etc and its record of employees a sophisticated DBMS is used.Who are the End Users? How many type s of End Users are there in DBMS?End User The one who uses the database, it may be that he/she only views the database or it may be that he/she makes the data entries. Make queries, etcThere may be different types of end user, for example Sophisticated these are the users who has a good knowledge in database and can make queries, with SQL manipulate data with DML (Data Manipulating Language)Specialized who makes application programs that interacts with the databaseNative only interacts with the database via some sophisticated programs