Answer To: database/DBFN212-Assessment-Brief-4-Reflective-Journal_T2_2021-Updated.pdf XXXXXXXXXXKent Institute...
Neha answered on Oct 15 2021
93751 - reflective journal/database.docx
Introduction
It is the reflective journal for 11-week course of the database. It discusses about the importance of database design, and we also studied about the database evolution of database from file system. Before using the data management, we need to understand the flaws present in the file system. Entity can be the person, place event or the thing about which we are collecting the data. Attribute is the characteristic of that particular entity. The relationship is the association among the entities. Data is the raw fact. It is not processed to provide the real meaning to the end user. The information is the result of processing raw data to achieve the real meaning. I was able to understand how we can find out all the required entities and then establish the relationship among them in the relational database model.
Week 1
This is the database course in which we studied about each, and every term related with the data. We try to understand the difference between data and the information which is the most important and significant part of it. It describes what the database is, it's different types and why it is the valuable asset for decision making. It discusses about the importance of database design, and we also studied about the database evolution of database from file system. Before using the data management, we need to understand the flaws present in the file system. After this we discussed about the major components of the database system and the main functions which can be performed by the database management system. The data in the current world is ubiquitous and pervasive. These are the characteristics of the data in today's world. The databases are used to make the data persistent and shareable in the secure manner. It provides specialised structure which allow the computer-based systems to store, retrieve and manage the data quickly. Data is the raw fact. It is not processed to provide the real meaning to the end user. The information is the result of processing raw data to achieve the real meaning.
Week 2
The data modelling can be defined as creating specific data model for the determined problem domain. The data model is the simple representation of complex real world data structures. It is used to support the specific problem domain. The model can be defined as abstraction of the complex real-world objects or the events. We cannot overstate the importance of data modelling. It allows us to have the communication and provide different views of the database. The data can be organised in different manners for different users. it provides abstraction to create the good database. Entity can be the person, place event or the thing about which we are collecting the data. Attribute is the characteristic of that particular entity. The relationship is the association among the entities. We can have one to many relationships, many to many relationships and one to one relationship among the entities. The constraints are the restrictions which are present on the data. So, the constraints are used to make sure that we can achieve data integrity in the database. It helps to create and enforce the exchange within the environment of the organization. We are able to provide brief, unambiguous and precise description of a policy, procedure, or principle. It helps to establish entities, relationships, and constraints.
Week 3
In the 3rd week we discussed about the logical structure of relational database model. We need to understand all the basic components of the relational model before utilising it into the solution. This week provides the explanation about contains, characteristics and structure of the relational table. We can use the relational database operators for manipulating the relational table contents. Explain about the purpose and the components of system catalogue and the data dictionary. I was able to understand how we can find out all the required entities and then establish the relationship among them in the relational database model. This content also describe how we can handle the data redundancy in the relational database model. This also its purpose of indexing a relational database. All these terms are very basic but most important part when we are implementing the database management system. The relational database model helps to provide logical representation of the data and the relationship among them. The logical is used to add a simple database design ologies. The logical view is provided by creating the data relationships on the basis of logical construct which is known as the relation. Each of the key has one or more attributes are used to remind the other attributes. Try to make sure that every row present in the table is uniquely identifiable.
Week 4
In the fourth week we discussed about the characteristics of entity relationship component. After this week I was able to describe how the relationships between the entities can be defined, refined and incorporated in the database design process. It also shows how the entity relationship diagram components will be able to affect the database design and its implementation. We need to understand the real world database design which is generally require the reconciliation of the conflicting goals. The conceptual database is used by the end user. Entities, attributes and relationships are the major components of database. We need to understand how we can create the correct entity relationship diagram for the implementation in the management system. The entity relationship management is related with the table not with the row in the relational environment. The entity is represented with the help of rectangle, and it contains the name of the entity. The entity has few characteristics like required attribute, optional attribute, identifier, domain, composite attribute, composite identifier and few others. The composite attribute can be subdivided to find out the additional attributes. The single attribute cannot be divided further. The single add attribute has single value and the multivalued attribute has multiple values.
Week 5
With this week I was able to understand the main extended entity relationship model. This week provides information about how the extended entity relationship model can be represented in the entity relationship diagram and the extended entity relationship diagram. We can use the entity clusters for representing multiple entities and the relationships present among them in entity relationship Diagram. It also helps to describe about the characteristics of good primary keys and how we can select them for the data. I learned how we can apply the flexible solutions for the special data modelling cases. We discussed about the enhanced entity relationship model. We discussed about the result of adding the more semantic constructs to the basic entity relationship model. We have entity super type and sub type in the entity model. The entity super type is the generic entity type which is related with one or more entity subtypes. It contains common characteristics. The entity sub type has unique characteristics of every entity subtype, and it contains the criteria to determine the usage. It is important that all the entities have different and identifiable type in the environment of the user.
Week 6
In this week the focus was only on normalisation. It is the most critical and complex part of the database management system. In this week we discussed about the normalization and why it is so important in the database design process. It describes about every normal form present in the normalization. We can have first rumble form, second normal form, 3rd normal form, BCNF and the 4th normal form. This week explains how the normal forms can be transformed from the lower normal forms to the upper normal forms. The normalization rules can be applied to evaluate and correct the structure of the table. We need to identify all the situations which ask for the d normalization to generate the information in efficient manner. The data modelling check list can be used to check whether the entity relationship diagram is able to meet the minimum requirements or not. The normalization is used to reduce the data redundancies data anomalies and assign the attributes on the basis of determination. The higher normal forms are much better than the lower normal forms. It is important that if the database is able to meet the requirements of 3rd normal form, then we can try to achieve the 4th normal form. The normalization is used to produce the lower normal form and it can result in increased performance and more data redundancy.
Week 7
In the 7th week we were trying to understand how the data can be extracted from the database. This week provides us guidance for retrieving the specified columns from the data ways about the data. We can apply the join on multiple tables in the single SQL query to retrieve the data. There is restriction on the data retrievals which are matching complex criteria. We learned about the aggregation of the data across the groups of rose. I also learned about creating the sub queries for pre-processing the data so that they can be included in the other queries. I discussed about the key principles to use the select queries. The SQL function has multiple categories which are data definition language, data manipulation language, data control language and transaction control language. The SQL is easy to learn, and it is the known procedural language. It has a very basic commentary which clothes less 100 words the fundamental types of the data are character data, numeric data and date data.
Week 8
In the 8th week we learned how we can utilise the SQL language for creating the tables and inserting data in it. In this week we used the structured query language for creating the table manually...