1. extent of the database improvement will be examined by the team with various number of business system choices. As per requirements and business designs the choices will be chosen to plan and actualize. Amid this stage, following necessities will be identified:
· Make a decision with least requirements in workplace.
· Number of alternatives options for each prerequisite of user
· The least prerequisite to fulfill in system.
2. Requirement specification- Once the prerequisite are cleared up that stage 2, methodology can be utilized to decide the necessities for the chosen BSO. Rational data analysis is made alongside identification of data model, data processing model and prototyping. All of the necessities for improvement process are resolved at this stage by means of the client meeting and support.
3. Technical system options- BSO can be dissected for the specialized arrangements and abilities to fulfill it in working environment. In the event that the choice is actually conceivable than all the specialized methodologies are distinguished to list the specialized necessities for the advancement of system. Technical necessities dependably have the impact of business constraints and capital to invest in system.
4. Logical Design-In this stage, team would need to plan the system with consistent stream of control and data. The logical design of proposed system is required for the accompanying reasons:
· It clears up what information will be utilized and how it will stream for the correct execution in the system. It represents normally with flow diagrams and relationship diagrams for different entities.
· It is required to record the textual data of user demands and requirements to demonstrate how they are being accomplished in system
5. Physical plan- The logical design of the system is accustomed to bring the system into reality. The physical system will be created by the logical diagrams and data presentation. Company will get full working system in this phase where the execution will be subject to three things-mostly on data storage improvement, data processing mechanism, performance and the characteristics of system as per clients need
An entity-relationship model (ERM) could be a theoretical and conceptual approach of showing data relationships in software development. ERM could be an info modeling technique that generates an abstract diagram or visual illustration of a system’s data that can be useful in designing a relational database. These diagrams are referred to as entity-relationship diagrams, ER diagrams or ERDs.
· Components of E-R diagram
6. Entity: It as an object that exist in. in Database en entity can be a single thing person, place or an object. Data can b store about such entities. Designee tool that allows the database administrator to view the relationships between several entities is called the entity relationship diagram. In database administration only those thing about which data will be captured or stored is considered an entity. Example of entity that I have is hotel room
7. Attribute: it defines the information about the entity that needs to be stored. For example if the entity is employee attribute could include name, employee ID, health plan enrollment and work location. An entity will have 0 or more attributes. Each of those attributes will apply to that entity. For example the employ id belongs to that employee entity alone. Attribute also have furthered refinements. Such as domain and key
8. DOMEAIN: The domain of an entity describes the possible values of attributes. In the entity each attribute will have only one value, which could be blank, as well as it could be a number, text, and date or a time. For example name, employee id, guest id, hotel name, location and so on.
9. Key: The key the unique identifier which identify the entity. A key is also a domain because it will have values. These values are unique to each record and so it’s a special type of domain. A key isnt always required, but it should be. In our example a unique key value ensures that the employee entity cannot duplicate social security number or employee ids.
10. Primary key. It is a unique key in datable table. There should be no null values. For example in hotel table an employee key is the primary key. So if the employee key the primary key each recorded in the employee id attribute should be unique.
11. Candidate key. Any key where with the help of it we are able to uniquely identify the record of a table. The candidate key would not have any null values in it. Which means the recorded of that particle candidate key should not be empty for example mail id and department phone number may be used as candidate key if they are not shared among others in workplace.
12. Forigne key: It is identical to primary key, since forigne key is basically a reference of primary key into another table. For example employee table has four attributes refereeing to employee id, first name of the employee, last name of the employee and the phone number of the employee. In the table employee id being reference from another table which is hotel table. So in employee table an employee id is known as the forigne key.
· Relationship: an entity could be related to each other with the relations. The relationships in ER diagram can be exists in the following style.
1. One to one relationship: One entity of a table is simply associated with one entity of another table. As an example, one car company could also be associated to just one car model.
2. One-to-many: One entity mat has relation with more than one entity in another table. As an example, a doctor would handle more than one patient.
3. Many-to-many (M: N): most of entities in table could also be associated with most of entities in another table. As an example, several students could also be learning several subjects. .