Define partial, alternate,artificial,compound &natural key, Database Management System

 

Partial Key: It is a group of attributes that can uniquely identify small entities and that are related to same base entity. It is sometime named as Discriminator.

 Alternate Key: All Candidate Keys remaining the Primary Key are called as Alternate Keys.

 Artificial Key: If no obvious key either compound or stands alone is available, then the last resort is to simply give a key, by assigning a distinct number to every occurrence or record. Then this is called as developing an artificial key.

 Compound Key: If no single data component uniquely identifies occurrences within a developed, then combining multiple components to make a distinct identifier for the construct is called as creating a compound key.

 Natural Key: When one of the data components stored within a construct is used as the primary key, and then it is known the natural key.

 

Posted Date: 7/30/2012 2:28:40 AM | Location : United States







Related Discussions:- Define partial, alternate,artificial,compound &natural key, Assignment Help, Ask Question on Define partial, alternate,artificial,compound &natural key, Get Answer, Expert's Help, Define partial, alternate,artificial,compound &natural key Discussions

Write discussion on Define partial, alternate,artificial,compound &natural key
Your posts are moderated
Related Questions
What are the disadvantages of file processing system? The drawbacks of file processing systems are a) Data redundancy and inconsistency b) Complexity in accessing data

sir we want er diagram of bank management system in this main menu option as new account,deposit amount,withdraw amount,all acount holder list,modify account,close account

What are the advantages of Logical Databases? It offers a simple-to-use selection screens.  You can change the pre-generated selection screen to your needs.  It offers check f

Define a property that is not a property of transactions? Ans: Concurrency is not a property of transactions

Describe Physical Data independence ? Physical Data Independence - It is capacity to modify the internal schema without having to change conceptual schema. Therefore, the exter

OBJECTIVES After going through this unit you should be capable to: Explain the File Based system and its limitations; Explain the structure of DBMS; Explain the

1.Suppose you are given a dataset that consists of a random sample of tasters, on which the following variables were obtained: (y) Zpref = taste preference for green beans store

How to Insert data in your table from another table? insert into e.g, To insert tuples from employee into N_emp created above, use following statement Insert into N_emp


What are the different approaches for database design? There are two basic approaches for database design which are as follows: Attribute driven: It compiles a list of att