Objective To recognize systematic steps required in building database To identify Conceptual, Logical & Physical designs relevance.

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Felix Fleming
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1 14 th September 2017

2 Objective To recognize systematic steps required in building database To identify Conceptual, Logical & Physical designs relevance Learning outcome Students would be able to use SDLC framework in building a database.

3 Building a database using System Development Life Cycle framework (SDLC) Building a House (Learning from the large project perspective) Landlord conceives plan for building structure required for future tenants Architect sketches or draws conceived plan (schematic diagram) with logical & technical tools to represent house Mason translates the architectural drawing to lay blocks, windows & doors to accommodate house tenants In an estate or a hostel porters are employed to accept tenants, provide security and maintenance of house Building a database Client conceives type of database required for business Application Database designer sketches or draws the E-R diagram or schema to represent records to be stored Database developer translates E-R diagram to create tables, define field (DDL) & keys to house records System administrators are employed to accept users/record, provide security & maintenance of tables during anomalies

4 Section 1: System Development Life Cycle -SDLC Basically Data Modeling is an Activity for Planning, Analysis & Building Project Identification and Contract Selection Project Initiation and Planning 4 Analysis Logical Design Physical Design Implementation *Building a Database using Project Mgt. principles Maintenance *SDLC Advantage: Helps meet system specifications or business needs of a client

5 Logical Design/Model (E-R diagram)

6 Logical design deals with gathering business requirements and converting those requirements into a model. The logical model revolves around the needs of the business (what type of records to store); although the needs of the business are used to establish the needs of the database. Output/Deliverables after completion of Logical design 1. Produce Entity Relationship diagram ( key ): Helps developer(s) know entities concern & their relationship 2. Draw Business process diagrams: Helps developers get idea of how data moves within client organization. 3. Document client/user feedback on 1&2: Helps contractor & client agree upon project final deliverables/expectations.

7 In a family, the wife is called by the name of the husband due to marriage relationship. One depends on the other. Likewise, the Entity-Relationship model provides a link for related records on two different tables. Clearly, one record on table-b depends on one record on table-a to exist.

11 ENTITY : Anything that exists. E.g. Each CHAIR is an Entity, Each person is an Entity (often corresponds to a row in a table) ENTITY SET: Group of similar entities forms an Entity Set. Example All persons. All buildings, All departments. ATTRIBUTES: The properties that characterize an entity set. E.g. Name, Address, Skill etc. (often corresponds to a field in a table) RELATIONSHIP: Association between two or more entities/tables. Example we may have the relationship that an Employee works in a Department (we relate using Primary key & Foreign key on a table) o RELEVANCE OF E-R MODELING: Is used for normalizing the database design at any point necessary. It is the main blueprint. Normalization may means taking away redundancy or dividing table into segment to make any modification easy in the database

Building Architects also have their symbols to guide the masons.

12 E-R Basic Notation Is used purposefully to communicate to developers what is expected. Building Architects also have their symbols to guide the masons. Relationships Line: illustrate an association between two tables/entities. In the physical data model, relationships are represented by stylized lines.

13 i) Use details provided to design a E-R diagram. 1. Books 2. First Name 3. Title 4. Written by 5. Author ID number 6. Mobile number 7. Author 8. ISBN 9. Price 10. Name

14 Physical Design/Model (Creating Tables)

Objective To translate E-R diagram in creating a table. Learning outcome. Students would be able to create and instantiate a table

28 th September 2017 Objective To translate E-R diagram in creating a table Learning outcome Students would be able to create and instantiate a table Physical design /Model (Creating Tables) BUILDING CONSTRUCTION