Section 2 Flashcards
Have you ever had trouble finding a document in a filing cabinet or folder that someone else organized?
The files may have been organized to meet that person’s needs, but not your own.
Data modeling attempts to capture the needs of the business users so that the resulting database is one that everyone can use.
When you are able to recognize and analyze information, you can better ………… how things work and potentially make them ……….
understand / better
For example:
−How to make the line at the food counter go faster
−How to successfully exchange an item at the store
−How to organize and keep track of your growing CD collection
Also, recognizing and analyzing information helps prevent …………. and ………….
mistakes / misunderstanding
For a business, this is important because it saves time and money
A conceptual model Is the result of completing the ………. ………. ……….
Data Modeling process
A conceptual model Addresses the needs of a business (what is …………. ………….), but does not address its implementation (what is ………… …………)
conceptually ideal / physically possible
A conceptual model:
- Is based on current needs but it may reflect future needs
- Captures the …………. and ……….. ………… of a business
- FYI
- functional / informational needs
A conceptual model: −Identifies :
- important ………… (objects that become ……… in database)
- ………… among …………
- entities / tables
- relationships / entities
A conceptual model: −Does not specify :
- ………….. (objects that become ………… or ………. in database)
- ………… …………. (attribute that becomes ………. ………. in database)
- attributes / columns / fields
- unique identifiers / primary key
A conceptual model is important to a business because it:
- Describes exactly the ………. ……….. of the business
- Facilitates …………..
- information needs
- discussion
A conceptual model is important to a business because it:
- Prevents ………… and …………..
- Forms important “ideal system” …………..
- mistakes / misunderstandings
- documentation
A conceptual model is important to a business because it:
- Forms a sound basis for ……… …….. ……….
- Documents the ………. (also known as the “business rules”) of the business
- physical database design
- processes
A conceptual model is important to a business because it:
Takes into account ……………… and …………. governing this industry
regulations and laws
A logical model is called an ……….. ……….. ………. and is illustrated in an …………
entity relationship model (ERM) / ERD
A logical model Includes all entities and relationships among them
R 2
A logical model
- Specifies all ………… and …….. for each entity
- Determines …………. …………
- Determines relationship ……….. and ………….
- attributes / UIDs
- attribute optionality
- optionality / cardinality
cardinality: the number of elements (= separate items) in a mathematical set