WebJun 18, 2024 · In relational database minimal super keys is known as -. Q3. Consider the following statements regarding key - (I) A super key is an attribute or combination of attributes that uniquely identify records in an RDBMS table. (II) A candidate key is a subset of a super key. (III) All super keys are candidate keys but vice versa is not true. In the relational data model a superkey is a set of attributes that uniquely identifies each tuple of a relation. Because superkey values are unique, tuples with the same superkey value must also have the same non-key attribute values. That is, non-key attributes are functionally dependent on the superkey. The set of all attributes is always a superkey (the trivial superkey). Tuples in a relation are by defi…
Can candidate keys be of different lengths? – Quick-Advisors.com
WebJul 28, 2024 · Are candidate keys minimal? A candidate key is a minimal super key or a super key with no redundant attribute. It is called a minimal superkey because we select a candidate key from a set of super key such that selected candidate key is the minimum attribute required to uniquely identify the table. Can primary key be composite? WebMar 4, 2024 · Correct Answer - Option 4 : Both Candidate and Primary Key A candidate key is a minimal super key or a super key with no redundant attribute. It is called a minimal super key because we select a candidate key from a set of super keys such that the selected candidate key is the minimum attribute required to uniquely identify the table. does it snow in yucaipa ca
DBMS Keys: Primary, Super, Candidate, Foreign - TAE - Tutorial …
WebMay 17, 2013 · Just found out very neat explanation: superkey: a set of attributes which will uniquely identify each tuple in a relation. candidate key: a minimal superkey. primary key: a chosen candidate key. secondary key: all the rest of candiate keys. prime attribute: an attribute that is a part of a candidate key (key column). nonprime attribute: a nonkey column WebMar 19, 2016 · Althrough, minimal subset of super key is either id or ssn. but both of them can be considered as candidate key. Primary Key : Primary key is a one of the candidate key. Example : Student(Id, Name, Dept, Result) … WebJul 1, 2024 · The attribute or set of attributes which uniquely identify each record (row) in a table are called candidate keys. In other words, the minimal super key is a candidate key. Primary... does it snow in zion national park