Average Rating 0 out of 5 stars. 0 votes.You must log in to submit a review.Pseudotransitivity,”If X → Y and[…]
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Functional dependancy closure,”Given a set of FDs, F, the closure of F is often notated as F+Given an existing set of FDs
Average Rating 0 out of 5 stars. 0 votes.You must log in to submit a review.Functional dependancy closure,”Given a set[…]
Read moretrivial vs non trivial functional dependancies,”Trivial functional dependencies are typically omitted from FD sets because they add little information.The more meaningful alternative to trivial FDs are non-trivial functional dependencies: FDs in which X → Y holds but Y is not a subset of X, such as CourseID → Topic
Average Rating 0 out of 5 stars. 0 votes.You must log in to submit a review.trivial vs non trivial functional[…]
Read moreNormalization,”A formal method for creating well designed relational databases involves normalization
Average Rating 0 out of 5 stars. 0 votes.You must log in to submit a review.Normalization,”A formal method for creating[…]
Read more1 NF,”Have no duplicate tuplesHave no multi-valued attributesBy definition, a valid relation will conform to 1NFData that do not conform to 1NF (e.g.
Average Rating 0 out of 5 stars. 0 votes.You must log in to submit a review.1 NF,”Have no duplicate tuplesHave[…]
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Average Rating 0 out of 5 stars. 0 votes.You must log in to submit a review.2 NF Be in 1NFHave[…]
Read more2NF to 3NF
Average Rating 0 out of 5 stars. 0 votes.You must log in to submit a review.2NF to 3NF Eliminate all[…]
Read moreHigher normal forms,”Several normal forms exist beyond 3NF including:Elementary Key Normal Form (EKNF)Boyce-Codd Normal Form (BCNF or 3.5NF)Fourth Normal Form (4NF)Essential Tuple Normal Form (ETNF)Fifth Normal Form (5NF)Sixth Normal Form (6NF)Domain/Key Normal Form (DKNF)Typically it is sufficient to have tables in 3NF to avoid most types of anomalies
Average Rating 0 out of 5 stars. 0 votes.You must log in to submit a review.Higher normal forms,”Several normal forms[…]
Read moreKey constraints,”A relation must have at least one candidate key such that for every tuple
Average Rating 0 out of 5 stars. 0 votes.You must log in to submit a review.Key constraints,”A relation must have[…]
Read moreMapping Aggregation,”Relationships involving aggregations should reference all necessary primary keys from inside the aggregationEx.STUDENT(StudentID, StudentName)COURSE(CourseID, CourseName)PROFESSOR(ProfID, ProfName)TAKES(StudentID, CourseID)TEACHES(ProfID, StudentID
Average Rating 0 out of 5 stars. 0 votes.You must log in to submit a review.Mapping Aggregation,”Relationships involving aggregations should[…]
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