01 Database Development Process.pdf

Database Development Process IT IM01: Advanced Database Systems Christine Joyce M. Carlos, MBusAn Ruth Ann G. Santos, MSIT Learning Objective At the end of the lesson, the students should be able to: a. Differentiate the stages in the database life cycle b. Understand the steps on how to design a...

Database Development Process IT IM01: Advanced Database Systems Christine Joyce M. Carlos, MBusAn Ruth Ann G. Santos, MSIT Learning Objective At the end of the lesson, the students should be able to: a. Differentiate the stages in the database life cycle b. Understand the steps on how to design a good database. 2 Lecture Outline Components of Information Systems Database Life Cycle (DBLC) The Design of the Database 3 Review Define the following: Data A piece of knowledge that can be interpreted Database A shared, integrated computer structure that stores a collection of data, as well as, metadata Metadata Data about the data DBMS Software systems that serves as an intermediary between the database and user; used to store, retrieve, define and manage data 4 Components of Information System Hardware Hardware: physical components of an information system Software: applications that carry out instructions on Process Software what to do Network Communication: Ability to exchange data and share resources among two or more devices Information System Database: Collection and organization of raw-facts People: users of Information Systems People Network Commu- Process: series of steps undertaken to achieve a nications desired outcome 5 Database Database Life Cycle The database life cycle Requirement (DBLC) is described as Analysis Design Stage the stages included for implementing a database, which begins Monitoring, with the analysis of the Modification and Logical Design requirements and ends Maintenance with the checking and Post - modification. Design Stage 6 Implementation Physical Design Phase 1: Requirement Analysis Data Requirement Specification Involves evaluating the details needed in an organization so that the database can be designed to produce the required information Interview both data producers and users Business objectives will dictate the database design 7 Phase II: Logical Design Creating conceptual models and normalizing data tables Conceptual model is a description of the structure of database usually represented by a Entity – Relationship (ER) diagram that shows the tables, fields, and primary keys of the database, and how tables are related (linked) to one another 8 Phase II: Logical Design Normalizing data tables is the process of applying increasingly stringent rules to reduce data redundancy and other problems related to design. 9 Phase II: Logical Design Ensures that the notional and logical data structure requirements are met Notional: Reflect the reality of the phenomena, their characteristics, and their relations Logical: Follow technical standards, remain accessible for modification, and efficient for data access 10 Phase III: Physical Design This stage aims to optimize the productivity of the database Finding ways to accelerate RDBMS performance. Extracting of data from database and writing data into it which are the slowest operations in RDBMS can speed up by manipulating some elements of database design. 11 Phase III: Physical Design Physical Structure: An acceptable database is when physical manifestation matches realities. Some components of the physical structure that need to be observed: Assertion: The data to be entered must be acceptable or valid. If we add a date, for example, its value and structure must be correct. Data presentation: It gives the specific type and size of data such as textual, imaginary, logical, numerical, etc. Data management and storage method: The more advanced the management and storage methods are, the less time is needed to monitor the database behavior. 12 Design Stage: Physical Structure of DB Data table: The file in table form represented by the entities or data sources Field: The table columns which are represented by the attributes. Record: The table rows, also known as tuple. Elementary item: Values per table cell. 13 Phase IV: Implementation During the implementation stage of the DBLC, the tables developed in the ER diagram (and subsequently normalized) are converted into SQL statements. These SQL statements are then executed in the RDBMS to create a database. 14 Phase V: Monitoring, Modification, and Maintenance A successfully implemented database must be carefully monitored to ensure that it is functioning properly and that it is secure from unauthorized access. The RDBMS usually provides utilities to help monitor database functionality and security. Database modification involves adding and deleting records, importing data from other systems (as needed), and creating additional tables, user views, and other objects and tools. As an organization grows, its information system must grow to remain useful 15  6 Steps in Designing a Database Declaration Identification of identifiers Requirement of entities such Establishment of Testing Data input Handling and their primary and relationships attributes foreign keys. Define the Once the Establish Show the Once the tables objectives of entities are Relationships connection are created and the database identified, between keys are in place, testing is that will be table relations required to the basis of structures ensure that the the database can be design does design. specified not cause any inconsistencies 16 THANK YOU 17