In this assignment, the company I will be working with is Villa Care Kenya Company which can be found in the undermentioned nexus hypertext transfer protocol: //www.villacarekenya.co.ke/ and is located in Kenya, Africa. Villa Care Kenya is a existent estate company located in Kenya and it started its operations in 1994. It specialises in sale and rental ofA a assortment of commercial and upfront residential belongingss especiallyA in and Mombasa and Nairobi. In add-on it besides specialises in sale of lands and sites. Having designed the company ‘s database for all its operations i have been requested to buy a suited database direction system to implement this database. Presently, this house is utilizing the traditional database system ; that is relational database direction system. This company aims at following tools which are efficient and already in the market to enable them present satisfactory and prompt consequences to their clients. In order to carry through their vision, this house needs to implementA A the suited database direction systems, which can enable better entree and storage of informations. There is limited usage of database direction system where most services are non rendered through the web, multimedia or image informations is limited, web direction systems are non available and synergistic and dynamic web is limited. In order to make this, i am traveling to analyze the different types of DBMS with their pros and cons, and supply a study proposing the suited DBMS for implementing in this company to its Managing Director.
As Villa Care Kenya Company is presently utilizing the RDBMS, I would urge them to implement ORDBMS. This is because RDBMS is non run intoing all the company needs. On the other manus, the company does non necessitate to implement a new system, that is OODBMS as this system is suited for more complex dealingss with longer minutess and for fabrication and designing houses. Hence go forthing us with ORDBMS, which i extremely recommend as it can be implemented parallel with RDBMS. The house will widen the demands required into RDBMS hence making the ORDBMS. These extensile demands are multimedia or image informations, web direction systems and synergistic and dynamic web. By implementing ORDBMS the company will cut down there costs and will non free any benefits of the former system. Most significantly, it allows the coder and stop user to utilize the object-oriented systems in parallel. As we all know, we all resist to alterations, this is reduced as ORDBMS is a loanblend of object oriented and relational theoretical accounts. ORDBMS is universally accepted unlike OODBMS which has a niche market. I did a comparing of both OODBMS and ORDBMSA A as follows:
- Data modeling comparing: They both support polymorphism, A complex objects and relationships, encapsulation, heritage and object individuality.
- Data entree ; both support adhoc question installations, schema development, pilotage, accessing and making relentless informations. On the other manus ORDBMS supports unity restraints while OODBMS does non back up unity restraints.
- Data sharing ; both support recovery and ACID minutess. OODBMS supports advanced dealing theoretical accounts where grade of support differs between merchandises ( this is non a needed functionality for Villa Care Kenya limited ) whereas ORDBMS does n’t back up advanced dealing theoretical accounts. Last OODBMS has limited support on security and positions whereas ORDBMS strongly supports security and positions.
- From the above comparing, both database systems provide the same functionalities but ORDBMS has extra functionalities which are a demand for this company.I have analyzed all the database direction systems and careworn recommendations for this company.
DATABASE MANAGEMENT SYSTEM ( DBMS )
.A shared aggregation of logically related informations with a designed description to run into an administrations information demands is called a database. DBMS has changed the manner many houses work, its the package thatA interacts with the database and user ‘s application programs.In add-on, itA facilitate the user to keep, make, specify and command entree to database.
There are three types of DBMS as discussed below:
RELATIONAL DATABASE MANAGEMENT SYSTEM ( RDBMS )
The RDBMS represents the 2nd coevals of DBMS.A Creation of RDBMS started in the late seventiess and include office entree. This came into being so as to enable
- Data independency of high grade.
- Data use linguistic communication enlargement.
- Significant evidences for covering with redundancy jobs, consistence and information semantics.
ADVANTAGES OF RDBMS
- Its easy for users to widen, entree and widen informations. New informations can be added to the original database without altering the bing application.
- It ‘s an first-class beginning of information.
- RDBMS has a simple logical construction, therefore its easier to pass on and understand informations.
- It ‘s suited for on-line dealing processing. RDBMS are flexible, and productive. They are flexible because when inputting information, the users do n’t hold to utilize predefined keys. Productivity is enabled by the fact that SQL is easier to larn, therefore less clip is consumed while carry oning developing Sessionss on how to utilize the RDBMS in an administration.
- It has data independency.
DISADVANTAGES OF RDBMS
- RDBMS ca n’t manage informations like digital, sound, images and picture as it does n’t hold adequate storage country to manage this characteristics. Largely RDBMS are created to manage templets and traditional fielded information.
- RDBMS does non work expeditiously with other linguistic communications outside of SQL. This includes SQL and Java.
- Due to the procedure of standardization, there is the creative activity of dealingss non matching to existent universe entities, this leads to existent universe entities been represented ill.
- There is semantic overloading as there is merely one concept for stand foring relationships between informations.
- Poor support for security, unity and general restraints. This indicates that there is invalidness and incompatibility of stored informations in RDBMS.
- Homogeneous informations construction. In RDBMS the tuple of a relation must dwell the doll property and values in a peculiar column must be an atomic value.
- This construction is non suited for existent universe objects with complex constructions as it leads to inefficient unnatural signifiers.
- There are limited operations as SQL does non let new operations to be specified as there is a fixed figure of operations in RDBMS.
- Impendence mismatch: There is deficiency of computational completeness in most informations use linguistic communications for RDBMS.
- TransactionA in the concern processing are by and large shortA lived and the concurrence control primitives such as two-phase lockup are non particularlyA suited for long-duration minutess, which are more common for complex design objects.
- Trouble in managing recursive questions: Atomicity and informations agencies that reiterating groups are non allowed in the relational theoretical account. As a consequence it is hard to manage recursive questions.
- There is deficiency of natural scheme revolution in RDBMS therefore taking to trouble in scheme alterations. To enable scheme alterations, database decision makers must alter the constructions of the database and modify plans that entree these new constructions.
- There is hapless navigational entree in RDBMS ( entree between single records ) . Navigational entrees are of import for many of the complex applications.
In RDBMS there is the complexness of mapping an object-oriented linguistic communication to a relational information base. RDBMS has been accepted for many concern applications including air hose reserves, order processing, banking and stock list control. Although RDBMS has been accepted by must concern applications, it has proved to be undependable for complex applications such as
- digital publication
- web direction system.
- Computer Aided Manufacturing ( CAM )
- Office Information system ( OIS ) and multi media system
- Synergistic and dynamic websites.A
The increased complexness of database applications led to the outgrowth of two new informations theoretical accounts ( OODBMS and ORDBMS.This development represent 3rd coevals DBMS.
OBJECT ORIENTED DATABASE MANAGEMENT SYSTEM
OODBMS is a system that enables query optimization and supports concurrence and recovery control, atomic minutess and continuity. In add-on, they support the storage of complex objects and enables efficient and faster retrieval methods. There is reusability of constituents as scheduling linguistic communications are used such as Java.
Examples of OODBMS are jasmine Object Database and Versant Object Database.
The OODBMS has the undermentioned mandatary characteristics
- It must back up complex objects by using builders to the basic objects.
- All objects should hold a alone individuality with property values which are independent to each peculiar object.
- Encapsulation must be supported ; this is achieved by guaranting that execution methods and informations are hidden in objects. Thus information that should be confidential ca n’t be accessed by anyone who is non permitted to make so.
- A subtype should be able to inherit methods and attributes from its ace type or ace category severally.
- It should back up dynamic adhering hence enabling overloading where a defined method can use to objects of different types.
- There should be extensile informations types, this will enable users to construct new types from the bing predefined types.
- It must be capable of pull offing really big databases, support concurrent users and question informations in a simple manner.
The OODBMS evolved so as to work out three countries that are debatable in RDBMS. That is long continuance minutess, version and scheme. These issues are addressed in OODBMS as follows
A dealing is a logical unit of work designed to transform the database from one consistent province to another. RDBMS can back up short continuance minutess but cant grip long continuance minutess which are found in complex objects e.g. in design and technology applications. This can really run for yearss or many hours, inorder to back up this long continuance minutess, different protocols from those used in RDBMS are required. The unit of concurrence control and recovery is logically an object in OODBMS and the normally used type of concurrence control mechanism used in OODBMS is Locking-based and this prevents conflict from happening.
Version direction is the procedure of keeping object development. This is critical as many applications require accessing the old province of an object and besides maintaining path of any alterations made to an object by assorted minutess.
ADVANTAGES OF OODBMS
It provides solutions to many advanced database applications.
Enriched patterning capablenesss ; It allows the “real world” to be modelled more inA a more realistic and natural representation of the existent universe objects. In OODBMS objects can be formed into complex objects as many relationships can be stored, this is one of the ruins found in RDBMS.
Extensibility: Allows formation of ace category that are shared with sub categories therefore cut downing redundancy within the system ; There is easier care of database and its applications because of overruling and reusability of categories.
Removal and imminence mismatch. A individual linguistic communication interface between DML and the scheduling linguistic communication helps in the turning away of imminence mismatch. This enables the riddance of the inefficiencies that occur in mapping declaratory linguistic communication to imperative linguistic communication e.g. SQL to C++ .
The usage of expressive Query linguistic communication enables the system to manage recursive questions ; this is enabled by the navigational entree from one object to another.
Schema developments are more executable in OODBMS due to tight matching between application and information. The scheme is more intuitive, better structured and gaining control more semantics of the application due to Inheritance and coevals.
It supports long continuance minutess unlike RDBM which supports short minutess.
Applicability to progress database application: RDBMS cant support CAD, CASE, OIS and multi media whereas OODBMS can back up this advanced applications.
Harmonizing to most benchmarks, OODBMS provides important betterment over provides important and this indicates that in OODBMS there is improved public presentation.
Lack of experience: It is limited to a little niche market and has non been to the full accepted. In add-on its more geared to the coder and non the terminal user.A
Most theoretical accounts lack a theoretical foundation as there is no universally set object orientated question linguistic communication and informations theoretical account.
Competition ; RDBMS and ORDBMS merchandises are more competitory than OODBMS.Both RDBMS and ORDBMS are already established in the market and uses SQLA which is an sanctioned linguistic communication, in add-on, this merchandises have tools which can back up both developers and terminal users hence doing them more favorable.
Encapsulation is compromised by query optimisation. Due to question optimization, information that should be kept confidential could be accessed by users who are non permitted to see this information.
Performance may be affected by locking an object degree particularly if locking is of an heritage hierarchy which as a consequence can besides be difficult to lock.
Due to complexness of OODBMS, they seem to be more hard to utilize and are more expensive. These complexness is due functionalities such as enabling long continuance minutess, scheme developments, arrow swizzling among others. As we can see from this study OODBMS has more functionalities as compared to RDBMS and therefore doing it more complex.
Most OODBMS have unequal security and position mechanism. Due to this single categories and objects cant be granted entree rights byA the user.
Due to RDBMS failing and rise of ORDBMS, RDBMS was extended with object-oriented characteristics giving rise to ORDBMS. There is a assortment of drawn-out relational theoretical accounts, all depending on the grade and manner extensions are made. But they all portion the same relational tabular arraies, query linguistic communication and object incorporation is the same. There extensions depends on the functionality of which each and every administration requires to be incorporated in their system. They store informations in the database but some of them can be able to hive away processs or methods.
ORDBMS indicates that the system integrate some impressions of “OBJECT” . Thus ORDBMS acts as a loanblend of OODBMS and RDBMS.
ADVANTAGES OF ORDBMS
ORDBMS resolves most of the failings of RDBMS as discussed before.
ORDBMS enables reuse and sharing taking to productiveness addition for the enduser and developer. The extension of the DBMS waiter to centrally execute standard functionality enables reusabilityA and allows this functionality to be shared by all applications.
The ORDBMS enables administrations to add the needed functionality in their existing database system. By adding this needed extensions, the administration spend less money, as compared to implementing a new system in the administration. Most significantly, the company does non lose the benefits of the database characteristics and maps presently in usage.
There is the compatibility of SQL ; 2008 criterion with SQL2 criterion, therefore doing it easier for administrations to do extensions on the RDBM and therefore can go on utilizing their bing systems, without doing major alterations.
In add-on terminal users and coders can utilize object-oriented systems in analogue.
Some of the RDBMS sellers include Oracle, IBM and M icrosoft.
DISADVANTAGES OF ORDBMS
- There is a batch of complexness in ORDBMS as its the meeting of object oriented theoretical accounts and relational theoretical accounts. Besides, this complexness is brought approximately by the fact that there is no standard manner of doing this functionality extensions.
- The increased costs associated with doing the extensions.
- Once the extensions are huffy, so the simpleness of the relational theoretical account in this instance is lost.
As Villa Care Kenya Company is presently utilizing the RDBMS, I would urge them to buy ORDBMS.
In add-on since the company is utilizing RDBMS, the new required functionality can be designed suitably in line with the company ‘s functional and non functional demand. This will be cost effectual for the administration as they do n’t hold to get down carry oning intensive preparation, because the users are already accustomed to the bing RDBMS and will bit by bit accommodate to the added new characteristics. This would be cost effectual. It will besides understate opposition to alter from the terminal users as the company is non altering the whole system.
By implementing ORDBMS, it will heighten:
Office information system: The company can utilize this functionalityA to command information within the administration, A this includes bills, paperss, electronic mails among others. All this information is critical to this company as it deals with selling and leasing of belongingss.
In add-on office information system can manage exposure and voice commentary. This can be used particularly when a user is asking about a certain belongings, A they can listen to the voice commentary and besides view the exposure fro m different dimensions. Presently, the administrations is non supplying good picture taking as users cant browse through the images.
Multi media systems: The company can utilize:
- Image informations where clients can be able to question utilizing graphical images of the characteristics that may be found in desirable belongingss ( such as bay Windowss or roof horticulture ) .
- Audio information where the client can utilize characteristics for the coveted belongings to find the noise degree from the close by traffic.
- Video informations: A client may question utilizing a picture characteristics of the coveted belongingss such as positions of the sea.
Synergistic and dynamic web sites: This can be usedA A enable users to seek for points that match their user defined standards, enable user to happen an point based on their customised specification and choosing a voiceover commentary giving inside informations of the coveted belongings.