Ads
related to: company database er diagram- Hundreds Of Templates
Browse Through Our Diagram
Templates Gallery And Sign Up Now.
- Start Diagramming
Free 7-day trial with unlimited
documents and premium features.
- Visio Alternative
Find all the functionality without
the high price tag.
- Lucidchart Integrations
AWS, G Suite, GitHub, MS Office,
Slack, BambooHR, Jive + more.
- Lucidchart For Enterprise
We Provide Intelligent Diagramming
For Enterprises. Know More!
- Lucidchart For Teams
Our Platform Helps Increase
Productivity Of Your Team.
- Hundreds Of Templates
Search results
Results From The WOW.Com Content Network
An entity–relationship model (or ER model) describes interrelated things of interest in a specific domain of knowledge. A basic ER model is composed of entity types (which classify the things of interest) and specifies relationships that can exist between entities (instances of those entity types).
A sample entity–relationship diagram One of the most common types of conceptual schemas is the ER ( entity–relationship model ) diagrams. Attributes in ER diagrams are usually modeled as an oval with the name of the attribute, linked to the entity or relationship that contains the attribute.
erwin Data Modeler (stylized as erwin but formerly as ERwin) is computer software for data modeling.Originally developed by Logic Works, erwin has since been acquired by a series of companies, before being spun-off by the private equity firm Parallax Capital Partners, which acquired and incorporated it as a separate entity, erwin, Inc., managed by CEO Adam Famularo.
The enhanced entity–relationship (EER) model (or extended entity–relationship model) in computer science is a high-level or conceptual data model incorporating extensions to the original entity–relationship (ER) model, used in the design of databases.
An entity–relationship model (ERM) is an abstract conceptual representation of structured data. Entity–relationship modeling is a relational schema database modeling method, used in software engineering to produce a type of conceptual data model (or semantic data model ) of a system, often a relational database , and its requirements in a ...
Thus, the "relation" in "relational database" refers to the various tables in the database; a relation is a set of tuples. The columns enumerate the various attributes of the entity (the employee's name, address or phone number, for example), and a row is an actual instance of the entity (a specific employee) that is represented by the relation.
The database schema is the structure of a database described in a formal language supported typically by a relational database management system (RDBMS). The term " schema " refers to the organization of data as a blueprint of how the database is constructed (divided into database tables in the case of relational databases ).
In the object-oriented application programming paradigm, which is related to database structure design, UML class diagrams may be used for object modeling. In that case, object relationships are modeled using UML associations, and multiplicity is used on those associations to denote cardinality. Here are some examples: [5]
Ad
related to: company database er diagram