Database Discovery Phase

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• entities are usually nouns
• relationships are usually verbs
• attributes are usually nouns that denote specific data

Names

• entity name is usually a singular noun
• relationship names have the form entity-verb-entity
  • verb should be active verb
• attribute names have the form EntityQualifierType
  • entity is name of the entity
  • qualifier describes the meaning of the attribute
  • type is chosen from a list of standard attribute types such as name, number and count

Example

Formal name	Informal name
Entity	Vehicle
Relationship	Vehicle-BelongsTo-Person
Attribute	VehicleLicenseNumber

Synonyms and Descriptions

• entities often have synonyms
  • should be documented in a glossary
• descriptions state the meaning of each entity, relationship, or attribute in complete sentences
  • should begin with an entity name
  • includes examples and counterexamples

Database Design

• usually move back and forth between steps

Conceptual Design Phase

Discovery of Entities, Relationships, Attributes

Step	Activity
1A	Identify entities, relationships, and attributes in interviews.
1B	Draw ER diagram.
1C	List standard attribute types in glossary.
1D	Document names, synonyms, and descriptions in glossary.