SAR Journal. Volume 2, Issue 1, Pages 39-46, ISSN 2619-9955, DOI: 10.18421/SAR21-06 March 2019. Application of ORACLE Database Design in the Creation of Information Systems for Small and Medium Enterprises Fadil Novalić, Hamza Kamberović, Muzafer Saračević University of Novi Pazar, D. Tucovića bb, Novi Pazar, Serbia Abstract – This paper describes the importance of the The access to the creation and the use of development of information systems for the needs of information systems should be comprehensive. In small and medium enterprises. The paper refers to order to successfully create and implement the other researches which prove the necessity of system, the starting point is modeling the actual introducing information systems in small and medium system. For this task are used some of the modeling enterprises. Oracle Database Design is presented as a simple and efficient manner to create a database on the tools in order to encompass all the necessary system grounds of which the information system has been entities and the relationships among them, while successfully developed. This paper provides a complete avoiding inclusion of unnecessary data, duplication example of database design. The conclusion provides a of data, placement of data in a place that is not the proposal for further researches that can be based on best for it, and similar defects in modeling. this paper. The course of work is determined by the flows in the development and application of information Keywords – Oracle, Information system, ERD, Database. systems in small and medium enterprises. Therefore, it is possible to say that the subject of this research is problem analysis of the businesses of small and 1. Introduction medium enterprises caused by the lack of use of In the era of accelerated development of information systems in the business, presentation of information and communication technologies and the tools for modeling the real system, and a their applications in many spheres of everyday life, description of an actual example of a system information systems have become a business's developed according to Oracle rules for modeling helping tool in almost every small and medium-sized real system and database design. enterprise. For the purposes of this paper was used the research on the importance of using Web application as a kind of information system in small and medium-sized enterprises. [1] The aim of the paper is to present the rules for efficient modeling of the real system according to the DOI: 10.18421/SAR21-06 requirements and for the needs of a particular https://dx.doi.org/10.18421/SAR21-06 company’s business. The realization of the Corresponding author: Fadil Novalić, mentioned goal of the paper should result with a University of Novi Pazar, D. Tucovida bb, Novi Pazar, good solution in creating a quality model of the real Serbia system which presents a small enterprise. Email: [email protected] The paper deals with modeling of the real system according to Oracle database design principles. Received: 22 January 2019. These rules manage to successfully bring designers Accepted: 05 March 2019. Published: 25 March 2019. to complete solutions, which sometimes may be complex. It starts from modeling the real system, © 2019 Fadil Novalić, Hamza Kamberović, which gives the conceptual model of the system. Muzafer Saračević; published by UIKTEN. This work is System entities are treated as entities, their licensed under the Creative Commons Attribution- characteristics, essential for the functioning of the NonCommercial-NoDerivs 3.0 License. system, represent the attributes of the entities, and The article is published with Open Access at relationships between them are related. Of course, www.sarjournal.com during all of this are taught the rules about optimal data structure, in order to keep data within the SAR Journal – Volume 2 / Number 1 / 2019. 39 SAR Journal. Volume 2, Issue 1, Pages 39-46, ISSN 2619-9955, DOI: 10.18421/SAR21-06 March 2019. structure running at the best location, avoiding "Objects-links diagram (ERD) is a graphical unnecessary duplication of data, etc. These rules are presentation of the associated entities and constraints defined through three forms of normalization. The that constitute the given design or project. As with conceptual model of the system is represented other visually-oriented design methodologies, it through the Entity Relationship Diagram - ERD, in provides a graphical summary of the database which the elements are represented by a standard, so structure that is very useful to the designer. "[5] that anyone who knows the standards of creating Based on the above, we realize that the ERD is these diagrams can understand them. After the based on important participants in the system conceptual model, the next step is moved to creating (entities), their features (attributes) and relationships a physical database, again according to the well- (relations). Of course, creating a conceptual data defined rules according to which the entities become model is not that simple. It is necessary to include in tables, the attributes become columns, and the links it all the necessary details. serve to define foreign keys by which tables are An entity is an object in a system, an event, or a interconnected.. concept. According to the Oracle database design rules, the entity name consists of a noun singular and 2. Oracle database design printed in capital letters. For example, CAR, ACCOUNT, CARPART, etc. Data describing the The design of database represents an interphase in entity are its attributes. The attribute is a specific designing the information system. In order for the piece of information that: describes an entity, information system to support the real-world quantifies an entity, qualifies an entity, classifies an functions of the system, it should make its image entity, and / or specifies an entity. Attributes have understandable for information technology. In other their own data type. They can represent a number, a words, the information system is a model of the real string of characters, a date, a file, and so on. For system. Through the process of developing the example, for an entity CARPART, the attributes can information system, real-world model systems are be a code, a name, a category, a date of production, a created on several levels. The first model obtained is price, etc. Instance is the notion that must be called a logical or conceptual model, and the mentioned in the story about the entities. It represents following one is a physical model, which implies a one copy of the entity. Each instance is uniquely database. The starting point in modeling the identified by one attribute or a combination of information system is to comprehend the real system multiple attributes. This attribute or combination of as a set of elements interacting with one another. attributes is called a Unique Identifier(s)-UID. The "The system is most generally defined as a set of UID has a different value for each instance, while objects (entities) and their interconnections. Objects other attributes can have the same value in multiple in the system can be some physical objects, concepts, instances, but only one value for one instance at one events, and more. Objects in a model of a system are time. For example, the instance CARPART can be a described through their properties (attributes) and set battery. It may have its own UID in the form of an relationships that connect these objects, as well as the article code and this code can not be assigned to any characteristic of those relations."[6] other car part. The attribute price may have the same Oracle Corporation uses the model of entity value for multiple car parts, but each car part can relations represented through a diagram when have only one price at a time. modeling the information systems. "Model of Entity Sometimes it makes sense to divide the entity into Relations (ER Model) is a list of all entities and subtypes. This can be the case when a group of attributes, as well as all relationships between entities instances has special properties, such as attributes that are of significance. This model also provides and connections that exist only for this group of basic information such as entity names, data types, instances. In this case, the entity is called an entity's and constraints. This model does not necessarily overhead, and each group is called an entity subtype. include an image, but usually the model presented For example, in car service, the entity SERVICE can through a diagram is very valuable."[4] be related to the sale of car parts and to the car's Oracle's conceptual model is called Entity service itself. These subjects in the car service Relationship Diagram - ERD. "The entities-links business have common attributes, but car parts must diagram, known as ERD, is a consistent tool that can have a price, while the price of the service itself will be used to represent the needs for data regardless of be based on the price of a working hour. which database type is used and even when the Oracle has set conventions on the presentation of database is not used at all." [2] the ERD elements. This allows a proper The ERD can also be called a data model, since it interpretation of the conceptual model of the system is the starting model of the information system. by the database designer. According to the above conventions, the entity and its attributes are placed in 40 SAR Journal – Volume 2 / Number 1 / 2019. SAR Journal. Volume 2, Issue 1, Pages 39-46, ISSN 2619-9955, DOI: 10.18421/SAR21-06 March 2019. an oval box. An entity is named in singular and 3.