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英文字典中文字典相关资料:


  • sql - Difference between superkey and composite key - Stack . . .
    A composite key is a key made of more than one column If a Super Key is made of more than one column it is also a composite If a composite key uniquely identifies a row it is also a Super key
  • Types of Keys in DBMS: Your Key to Database Success
    Understanding the various types of keys is essential for designing a robust and well-structured database There are eight Types of Keys in DBMS These keys included the primary key, foreign key, candidate key, super key, alternate key, composite key, unique key surrogate key
  • Surrogate Keys, Natural Keys, Candidate Keys, Composite Keys . . .
    A primary key that made up of more than one attribute is known as a composite key Example - [ EMPLOYEE_ID and EMPLOYEE_SSN_ID ] can together be treated as (one of) composite keys Another combination can be [ EMPLOYEE_ID, EMPLOYEE_SSN_ID and EMPLOYEE_DEPT_ID ]
  • How to Identify Keys and Superkeys in Functional Dependencies
    To find superkeys that are not keys, include additional attributes beyond the minimal key For example: A,B, C and A,B, D are superkeys because they include the key AB and additional attributes, but they are not minimal
  • terminology - Differences between key, superkey, minimal . . .
    Composite key or concatenate key: A key with > 1 columns Usually implies "composite primary key", although "composite alternate key" is also a thing Sort or control key : A key used to physically sequence the stored data
  • What is a Super Key in DBMS| Scaler Topics
    There are various classes of keys in DBMS Some of them are: A Super Key is essentially just a key, i e it can uniquely identify all the attributes in a database A Composite Key is a key that contains more than one attribute In the student table mentioned above, the key – (Section, Roll Number) is a Composite Key





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