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DATABASE REPORTASSIGNMENTSTUDENT
CONTENTSMILESTONE 1.........................................................................................................................2TASK 1..................................................................................................................................2NEED FOR DATABASE IN COMMERCIAL ENVIRONMENT.............................2NEED FOR DATABASE IN NON-COMMERCIAL ENVIRONMENT...................3TASK 2..................................................................................................................................3TASK 3..................................................................................................................................4TASK 4..................................................................................................................................5ER DIAGRAM.................................................................................................................5ENTITY TYPES AND KEYS.........................................................................................6ASSUMPTIONS...............................................................................................................8TASK 5..................................................................................................................................9MILESTONE 2.......................................................................................................................14TASK 6................................................................................................................................14TASK 7................................................................................................................................16TASK 8................................................................................................................................17REFERENCES.......................................................................................................................18
MILESTONE 1TASK 1Critically evaluate the features and importance of DBMS in commercial and non-commercial environment.Commercial EnvironmentNon- commercial EnvironmentBanksGovernment BodiesNHS-HospitalsLibrariesEducational SectorsChurches and ReligiousOrganizationsTelecom SectorHome OfficeWeb IndustriesSecurity IndustryDVLA/TV LicensesCharity OrganizationsAviation IndustryNEED FOR DATABASE IN COMMERCIAL ENVIRONMENTWhen it comes to commercial environments such as banks, web industries, aviation etc. thedatabase is used to save historical records, maintain current records, setup up the security ofdata by controlling the data access. Above all of them, keeping the data organized in the formof tables.Apart from this the data present in the database can be used to build data warehousefor the commercial industry. Thus will help in mining the data and extracting usefulinformation for future purposes such as expanding the business. For example aviation canhave its own data warehouse built from its various databases to find growth patterns. In caseof educational sectors, the database can be used to store records of student of past 20-30 yearssuch as details, roll number etc. for future references, rather than keeping them on paper.In this way we can say that databases are of high importance nowadays. The database usedare licensed ones and have large no. of features of data handling. Advantages they provideare:1.Data security2.Data integrity: by keeping only valid changes3.Data organization4.Controlled access of the data via permissions and much more.
NEED FOR DATABASE IN NON-COMMERCIAL ENVIRONMENTWhen it comes to non-commercial databases, the use is simple rather than being complex. Itis used for simple storage and retrieval of data. In non-commercial organizations such asLibraries, Churches and Religious Organizations, Home Office etc. just need to store data,manipulate it, calculate totals, retrieve data or generate reports if needed. For example librarywill have data about the books, their publisher, who issues it and when etc.All these data are not of high importance and thus the database used with them is a non-commercial which is available free of cost. The data records may be just a few hundreds ascompared to commercial databases which have records in millions and need high securitywhich is required less in the non-commercial one. The data is not very critical and of not sohigh importance. Thus database act as a basic component for storing data, daily smalltransactions etc., rather than keeping records on paper.TASK 2The key issues are:1.INTEGRITY:it refers to the accuracy of the data. In case of databases, to achievethis accuracy, certain constraints are used called the database integrity constraints. Forexample, setting the field as “not null” will ensure that the table’s field doesn’t acceptnull values. These constraints helps us to design the database as per the logical designdecided and in the sequential manner. In other words we can say that “designingcomplete database integrity is designing a complete database integrity constraint”.Some of the integrity constraints that help in storing accurate values are: [4]a.Uniqueb.Not nullc.Referential : primary key, foreign keyThe database integrity helps in the following ways:a.Preventing illegal users from addingnon-semantic datab.Handling the transactions by achieving the transaction rules.c.Reducing the complexity by use of primary key and foreign key.d.Helps in finding errors and improves the testing software/database testing results.2.SECURITY:In databases, security is one of the most important factors. Use ofdatabase is done to organize the data and then applying restricted access to it so that itcan be protected from varied illegal sources. This is done by setting up the user roles
and read, write, and execute access permissions on the database for enabling onlyauthorized data modifications.3.CONSISTENCY:it is one of the acid properties that ensures that the changes madeby the user to any instance of the database are right and consistent with reference tothe other values present in the database related to it. This property is used to setup thepre, post and current conditions in a consistent manner. For example if the userdeposits money in its account, this update remain consistent and changes are made touser account and bank’s amount as well. In simpler words we can say that either allchanges occur or none. The database is not left in an inconsistent state. [5]4.RECOVERY:this property enables to create recovery options for the situationswhen the data can be lost or changes may not be permanent. For this purpose, redoand write ahead logs are created so that the changes made after transaction or thevalues before transaction can be recovered, i.e., rolling back of the entire transaction.5.CONCURRENCY:Concurrency is a mechanism in which we control the transactionmechanisms. When to transactions occur at the same time and access the sameresource, then concurrency control is applied over them so as to control the deadlockor avoid inconsistent changes. Using the database mechanism. We assure that on atable or records, only one user commits the changes at once. This helps in maintainingthe integrity and consistency of the data present. This is achieved by locking the databeing used by a transaction, so that no other transaction interferes with it.6.APPLICATION OF DATABASE WITHIN ORGANIZATION:the database isused to store and manage information within the organization. It is an appropriate wayto manage large amount of data in an organized way rather than keeping themtraditionally on papers. Nowadays, database acts a backbone for the applicationsoftware.TASK 3When designing a software, a database is usually considered as a fundamental component ofthe information system, especially for the commercial systems. Thus we can say thatdesigning the database is also a part of the overall software development lifecycle. [6]The diagram below shows that how the database design is a part of the software development
lifecycle.The phases of Database Design and Database Implementation present in the in the middle ofthe picture are the phases that are used for development of the database. The other phases arebriefly described. Firstly all the needs are analysed for the databases and all the requirementsare documented before the actual design begins. Next on the basis of the requirements, thelogical diagrams are created so that the tables can be designed accordingly, reaching the finalimplementation then. The phases are described below:1.Database PlanningIn this phase, we realize the information in a very effective and efficient way. The needs to be
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