It is used to graphically represent entities in a database and show their relationships. The latter, is another form of representing entities but in table form. It is a 2-dimensional table showing columns as entity names and rows as attributes. Both are uniquely used in designing databases. Since both come handy in even if that technique is bested by the other one. This analysis aims to determine whether what database designers, especially students who are learning this subject, use in creating their database designs, why do they prefer that technique rather than he other one and what problems do they encounter in using either of the two.
Entity-relationship Diagram (RED) An entity-relationship (ERE) diagram is a specialized graphic that illustrates the relationships between entities in a database. ERE diagrams often use symbols to represent three different types of information. Boxes are commonly used to represent entities. Diamonds are normally used to represent relationships and ovals are used to represent attributes. Entity Relationship diagrams (also known as E-R or ERE diagrams) provide database designers with a valuable tool for modeling the legislations between database entities in a clear, precise format.
An Entity- Relationship diagram (RED) typically serves as the main deliverable of a conceptual data model. While newer approaches to E-R modeling have developed, the E-R approach is still cited by some professionals as "the premier model for conceptual database design". An RED is a logical representation of an organization's data, and consists of three primary components: Entities - Major categories of data and are represented by rectangles. Attributes - Characteristics of entities and are listed thin entity rectangles. Relationships - Business relationships between entities and are represented by lines.
Relational Data Model The relational data model represents data in the form of tables. The relational model is based on mathematical theory and therefore has a solid theoretical foundation. However, we need only a few simple concepts to describe the relational model; and it is therefore easily understood and used by those unfamiliar with the underlying theory. The relational data model consists of the following three components: 1. Data Truckee - data are organized in the form of tables with rows and columns. 2. Data manipulation - powerful operations (using SQL language) are used to manipulate data stored in the relations. . Data integrity - facilities are included to specify business rules that maintain the integrity of data when they are manipulated. ACTUAL COMPARATIVE ANALYSIS Research design This study used the descriptive method of research utilizing a survey to get information on what method is more easy to use when it comes to the implementation and conceptualizing the database. Participants The respondents are the students from Polytechnic University of the Philippines. We prefer to select our respondents from College of Computer and Information Management System and Database Administration.
A total of 12 respondents answered the survey. Data collection plans TASK SOURCES SCHEDULE To be able to get the response with regards on how they conceptualize their Database 3rd year IT students from College of Computer and Information System. October 12, 2013 Analysis of Data Results of the survey October 13, 2013 Interpretation of data Finalize the gathered data Interpretation of Data Question 1: What do you prefer to use: Converting RED to Relation (Normalized) or Relation (Normalized) to RED? FACTORS FREQUENCY PERCENTAGE 7 58. 3% RELATION to RED 5 41 . % TOTAL 12 100% 7 (58. 3%) respondents answered they use RED to Relation process and 5(41 . 7%) respondents answered they do Relation to RED process. Question 2: Why do you prefer that method? Most of the respondents preferred the conversion of RED to Relation because it follows the right way in developing an efficient database design. Along the way you've been normalizing without noticing and moving RED to Relation would be much easier or them, considering that they have already checked and tested the dependencies and referential integrity constraints.
Another reason, according to the respondents, is that simply because it is the traditional way and it is much easier than the other way around. Some respondents preferred the conversion of Relation to RED because they say that it is easy to make a relationship of tables when the data in a database are efficiently organized. It is convenient to create an RED with an existing relational data model and it is easy to normalize when the entity is in the form of a relation. Some also find this easy and more understandable. Question 3: What problems do you encounter in converting RED to Relation?
We asked the respondents to state the problems they usually encounter during the conversion of RED to Relation. Some say that they have difficulties in the relationship particularly in placing the cardinality. Conflict regarding the derived attributes and some Just say that it gets complicated along the way. Question 4: the conversion of Relation to RED. They say that there are tables that do not need a relationship or excess tables or data. They come into a state where they keep on normalizing while we are on the process of implementing.
They also have trouble in breaking down large entities and placing the foreign keys. SIGNIFICANCE OF THE STUDY Since two distinct techniques exist in creating database designs, it is common to have a "favorite" between the two. It became inevitable not to compare the two - Relations and RED. Though both are useful and have their own solving style properties, there exist a technique which is favored by most. This paper aims to determine whether what technique is mostly used by database aerators/designers especially students who may have a hard time choosing a technique to use.
This paper analyzes the results from surveys taken beforehand to show the different factors making the technique less usable or more usable to students. Also, this paper analyzes the difference between the two identities, showing each other weaknesses and constitution based on the survey performed. Entity-relationship Diagram (RED) - is a specialized graphic that illustrates the relationships between entities in a database. Relational Data Model - represents ATA in the form of tables.
Entities - Major categories of data and are represented by rectangles. Attributes - Characteristics of entities and are listed within entity rectangles. Relationships - Business relationships between entities and are represented by lines. Data structure - data are organized in the form of tables with rows and columns. Data manipulation - powerful operations (using SQL language) are used to manipulate data stored in the relations. Data integrity - facilities are included to specify business rules that maintain the integrity of data when they are manipulated.