Custom essays on Factors to consider when choosing a database management system

The development of contemporary project is mainly carries out through the usage of the databases like Oracle, IBM DB 2, Informix, Borland Interbase Server, MS SQL Server, Cache, Lotus Notes/Domino, MySQL and some others. At the same time, the usage of a DBMS Microsoft SQL Server makes about 62% of general DBMS choices. IBM and Oracle are deservedly regarded as leaders in the field of database management systems. The IBM first introduced the concept of relational database and developed SQL. Achievements of Oracle (outside the mainframe market) may include the release of the first commercial DBMS that supports SQL (1979), the first client-server version (1987), the first 32-bit (1983) and 64-bit (1995) versions, as well as the first commercial DBMS, transferred to a Linux operational system (1999) (Rob & Coronel, 2007).
Generally speaking, the list of requirements for the database management system used in the analysis of an information system may vary depending on the goals of the company. Nevertheless, it is possible to distinguish several groups of factor influencing the choice of a DBMS. They include: data modeling; architecture peculiarities and functionality capabilities; system performance control; peculiarities of application development; performance; reliability; working environment requirements; and other mixed criteria. Further, each group of factors is considered separately.

Data modeling:
– Applied model of data. There are many data models, the most common of which are hierarchical, network, relational, object-relational and object. The question of applying one or another particular model should be resolved at the initial stage of designing the DBM system.
– Triggers and stored procedures. Trigger presents a database program launched whenever the database is transformed through insertion, changes or deletion. Triggers provide the check on the correctness of any changes before these changes will be accepted. A stored procedure is factually a program that is stored on the server and may be recalled by the client. Since the stored procedures are performed directly on the database server, this provides higher performance in comparison with the process when the same operations are performed through the means of the database client. For the implementation of triggers and stored procedures, various software products use different tools (Grineva & Grinev, 2007).
– Search tools. Here it is important to mark that some modern database management systems have integrated additional instruments for contextual search.
– Required data types. In this aspect, two independent criteria should be taken into account: 1) the basic or fundamental types of data built into the system, and 2) the possibilities for the extension of data types. While the declination of basic sets of data types in modern DSM systems from a certain standard is typically insignificant, the mechanisms of data types extension in the systems of one or another producer differ a lot (Connolly & Begg, 2009).
– Implementation of the data-query language. All the contemporary systems are compatible with the standard data access language SQL-92, but many of them realize one or other extensions of this standard (Rob & Coronel, 2007).

Architecture peculiarities and functionality capabilities:
– Mobility. Here, the level of mobility means the level of independence of the system from the environment in which it operates. In this case, the environment includes both the hardware and software (operating system).
– Scalability. Selection of the DBMS should involve in issue of whether the system is consistent with the growth of information system, while this growth can be manifested in the increase in the number of users, the volume of stored data and the amount of information processed (Connolly & Begg, 2009).
– Depersiveness. The main reason for the application of information systems based on databases is the desire to unite the views of all the information concerning the organization and produced by it. The most simple and reliable approach is centralization of data storage and processing on a single server. Unfortunately, this is not always possible and finally forced to use the distributed database. Different systems have different ability to manage distributed databases (Rob & Coronel, 2007).
– Networking abilities. Many DBM systems allow usage of a wide range of network protocols and services for business and administration.
System performance control:
– Computer memory provisioning. The system may be able to control the usage of both memory and disk space. In the second case, it can be expressed, for example, in the compression of databases, or deleting redundant files.
– Auto-configuration. Many modern DBM systems include the possibilities of self-configuration, which typically rely on the results of the activity of services with self- diagnostics performance. This feature allows identifying the weaknesses in the system configuration and automatically configures it for maximum productivity (Connolly & Begg, 2009).

Peculiarities of application development:
– Many DBMS manufacturers also produce application development tools for their systems. Typically, these tools help to implement all the capabilities of the server in the best way, so in the analysis of DBMS the possibilities of application development tools should also be considered (Pratt & Adamski, 2007).
– Design tools. Some systems have automatic design tools for both databases and applications. Design tools from different vendors can vary significantly.
– Multilanguage support. Supporting a large number of national languages broadens the scope of the system and applications built on its basis.
– The possibility of developing Web-based applications. When developing various applications it often becomes necessary to use the opportunities of the Internet environment. Developing means of some manufacturers have a great set of tools for building applications for Web (Rob & Coronel, 2007).
– Supported programming languages. A wide range of the used programming languages ensures the system’s high accessibility for developers, and also can significantly affect the processing speed and functionality of the created applications.
Performance:
– TPC rating (Transactions per Cent). There are many various means for testing the performance, and many test ratings can be applied. One of the most popular and objective ones is the TPC analysis of systems performance. Actually, the TPC analysis examines the composition of DBMS and the hardware, on which this DBMS works. The TPC index is the ratio of the number of enquiries being processed for a certain period of time to the cost of the entire system (Pratt & Adamski, 2007).
– The possibilities of the parallel architecture. There are at least two approaches for the parallel processing of data: the parallelization of the processing of enquiries sequence for several processors, or using several client computers operating with one database, which are united into the so-called parallel server.
– Possibility to optimize enquiries. When using non-procedural query languages their implementation may be suboptimal. Therefore, it is necessary to accomplish the process of query optimization, i.e. choose the method of performance, when on the initial submission of an query through its syntactic and semantic transformations a procedural plan of query execution is produced, which is the most optimal plan for the existing database management structures.
Reliability:
The concept of reliability of the system has many meanings; it includes information safety independent of any failures, unfailing performance of the system under any conditions, providing protection of data from unauthorized access, etc.
– Failure recovery. In the emergence of hardware or software failures, the integrity and efficiency of the entire system may be violated. Often the viability of the system depends on how effectively the mechanism of failure recovery is planned.
– Backup. As a result of a hardware failure an information carrier can be partially damaged or disabled and the data recovery is impossible, if the backup of a database or its part was not provided. Backing up also helps in situations when there is a logical failure of the system, such as the mistaken removal of tables. There are many methods for data backup (storage of one or more copies of the entire database, storing a copy of its part, copying the logical structure, etc.). Often, the system is capable of using several of these methods (Jajodia, 2001).
– Rollback changes. When executing a transaction a simple rule is applied: either the transaction is executed completely or not executed at all. This means that in case of failures, all the results of the incomplete transactions must be canceled. The mechanism of the rollback may have various speed and efficiency.
– Multi-level protection system. The information system of any organization almost always includes secret information, therefore, to prevent unauthorized access the service of users identification is used. The level of protection may be different. Apart from direct identification of users when they log into the system, a mechanism of data encryption in case of its transmission over communications lines can be applied (Jajodia, 2001).
Working environment requirements include supported hardware platforms, minimum requirements for equipment, operating system under which the database management system is able to work, and the maximum size of addressable memory (Pratt & Adamski, 2007). Since almost all modern systems use their own file system, the important factor is what the maximum amount of memory they can use is.
Mixed criteria:
– The quality and completeness of the documentation. Unfortunately, not all systems have a full and detailed documentation.
– Localization. The possibility of using national languages is not fully implemented by all systems.
– Value formation model. Typically, DBMS manufacturers use specific models for value formation. For example, the cost of one and the same product may vary greatly depending on how many users will work with it.
– Producer stability and popularity of DBMS.
While developing databases or applications using the databases, the following factors also influence the selection of a specific DBMS: system positioning by the company; average number of users of the system, connected to the database; most typical and predictable operations in the database; average amount of data and the dynamics of its increase; outlook for company’s business and system development; cost of system implementation and ownership. The cost of operation is determined by many factors; the main of them are the cost of licenses, requirements for server hardware and, consequently, the cost of the necessary server.
Once the necessary system functions and the budget for the project implementation are determined, there remains one important question concerning who will actually choose this system? Let us consider the possible options starting with the least effective, which is a personal point of view.
1. The selection of a system is trusted to the system administrator. The argument is quite simple: he knows the software, so he will find a good system. But it is quite a dangerous decision. In practice, one may face the fact that the system administrator has no desire to look for a new “headache”, because the system will become a new responsibility for him. It must be set up, it must be studied and the staff on each issue will first of all address to him. That’s why often the system administrator deliberately delays selection of system, and having selected a convenient system, it appears that the system is convenient for him only, as it works on the operating system and database management system that are convenient for him. The convenience for users or the realization of functional possibilities fall to the background.
As a result, the system is selected; the administrator has performed his task and know that the system it not problematic for him, but how effectively it will be used by the staff and will it solve tasks of the management remains a question. There is a very big chance that the system will never be launched into the real work or will work in no more than 50% of its capacity (Rob & Coronel, 2007).
2. The selection of a system is trusted to the outside professionals. The argument is again simple: they are professionals; there are contractual responsibilities on the system selection, which must be fulfilled. Case in generally not bad, because the selection will indeed be professional, for the specific tasks of a company with all the standards and latest trends accounted. But for the most part, the outside specialists are partners of various system vendors and even if the selected system is fully fit for the task of the management and is user-friendly, it does not mean that there is no equivalent for less money or the equivalent with a greater set of functions. The selection cannot be called objective, because such experts get their reward from the system supplier, and they are interested in it not less than in the fulfillment of contractual responsibilities with the customer.
As a result, even satisfying the needs of the customer, the system may prove to be not the best option. Therefore, if a company addresses outside experts, there is a good reason to make sure that they do not have arrangements with suppliers or developers of management systems; a good thing is to run a parallel search of the system, and one should never be afraid to criticize the system proposed by the outside professionals (Rob & Coronel, 2007).
3. Working group formed among the staff of various levels. In our opinion a good option is to form a group of specialists, which would include one specialist for every task put by the organization management. Thus, one will get a system that not only implements one’s demands but is also useful for the direct users. Participation of members in selection the system increases the chances that the system will actually be used, rather than be installed on the server of the system administrator.
Of course, this option has many disadvantages too. For example, while the selection of system only the current tasks will be taken into account, not looking ahead. Therefore, ideally, it is better to select the system using a mixed type, that is, involving both, the organization’s own experts and the outside professionals into selection of the system. Then the selection will be as objective as possible, and the system selected will work for many years, opening up new opportunities for the development of the company (Rob & Coronel, 2007).
Selecting a database management system for the project is one of the most important tasks in developing the system, since the correctness of this choice provides the most complete satisfaction of the current and future needs. Individual selection of database management system in the development of the project allows creating systems that are successfully employed in industrial conditions.
Thus, the comparison of different DBM systems is a laborious task. Nevertheless, a clear comparative analysis on the basis of the above mentioned criteria in any case will help rationally choose a suitable system for a specific project or company. The list of factors helps realize the enormity of the task and execute it with adequate setting. It should also be noted that in practice, the decision on the use of a particular DBMS is typically taken by the head of the company, who may mainly rely on non-technical criteria. A special role is performed by such minor factors as advertising and promotion of the developers of a particular DBMS, the usage of specific systems in other enterprises, their price, availability of technical support, regular update, detailed documentation, etc.
As recommendation, the following rule can be applied: if a group of developers has sufficient financial capacity and if the potential client is also able to purchase the required number of licenses, the absolute preference should be given to commercial database management systems. If the financial capabilities of both developers and consumers of information system are limited, the DBMSs could be chosen, which have a sufficient level of stability and performance corresponding to the level of their price.

References:

Connolly, T.M., & Begg, C.E. (2009). Database Systems: A Practical Approach to Design, Implementation and Management (5th ed.). Addison Wesley.
Grineva, M., & Grinev, M. (2007). Query triggers for XML DBMS: Efficient implementation based on shadow mechanism. Programming and Computer Software, 33(4), 204-213.
Jajodia, S., Atluri, V.; Keefe, T.F., McCollum, C.D., & Mukkamala, R. (2001). Multilevel secure transaction processing. Journal of Computer Security, 9(3), 165-195.
Pratt, P.J., & Adamski, J.J. (2007). Concepts of Database Management (6th ed.). Course Technology.
Rob, P., & Coronel, C. (2007). Database Systems: Design, Implementation, and Management (8th ed.). Course Technology.