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2. Superkey - Wikipedia

   en.wikipedia.org/wiki/Superkey

   A candidate key (or minimal superkey) is a superkey that can't be reduced to a simpler superkey by removing an attribute. [ 3 ] For example, in an employee schema with attributes employeeID , name , job , and departmentID , if employeeID values are unique then employeeID combined with any or all of the other attributes can uniquely identify ...

3. Candidate key - Wikipedia

   en.wikipedia.org/wiki/Candidate_key

   A candidate key, or simply a key, of a relational database is any set of columns that have a unique combination of values in each row, with the additional constraint that removing any column could produce duplicate combinations of values. A candidate key is a minimal superkey, [1] i.e., a superkey that does not contain a smaller one. Therefore ...

4. Fourth normal form - Wikipedia

   en.wikipedia.org/wiki/Fourth_normal_form

   Fourth normal form (4NF) is a normal form used in database normalization. Introduced by Ronald Fagin in 1977, 4NF is the next level of normalization after Boyce–Codd normal form (BCNF). Whereas the second , third , and Boyce–Codd normal forms are concerned with functional dependencies , 4NF is concerned with a more general type of ...

5. File:Formal Logic.pdf - Wikipedia

   en.wikipedia.org/wiki/File:Formal_Logic.pdf

   You are free: to share – to copy, distribute and transmit the work; to remix – to adapt the work; Under the following conditions: attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made.

6. Second normal form - Wikipedia

   en.wikipedia.org/wiki/Second_normal_form

   Second normal form (2NF), in database normalization, is a normal form. A relation is in the second normal form if it fulfills the following two requirements: It is in first normal form. It does not have any non-prime attribute that is functionally dependent on any proper subset of any candidate key of

7. Enhanced entity–relationship model - Wikipedia

   en.wikipedia.org/wiki/Enhanced_entity...

   The MySQL Workbench offers creating, editing and exporting EER Models. Exporting to PNG and PDF allows easy sharing for presentations. Skipper allows users to create, import and export from object–relational mapping (ORM) schema definitions to editable EER models. SAP PowerDesigner [3] is a complex tool for modelling and transforming ...

8. Super key - Wikipedia

   en.wikipedia.org/wiki/Super_key

   Upload file; Search. Search. Appearance. Donate; ... Super key may refer to: Super key (keyboard button), modifier key on keyboards; Superkey, database relation

9. Natural key - Wikipedia

   en.wikipedia.org/wiki/Natural_key

   The advantages of using a natural key to uniquely identify records in a relation include less disk space usage, the natural key is an attribute that is related to the business or the real world so in most cases, it is already being stored in the relation which saves disk space as compared to creating a new column for storing the surrogate key.