Domains, Database Management System

A domain is a set of permissible values that can be given to an attribute. So each attribute in a table has a definite domain. Values to these attributes cannot be assigned outside their domains.

In the example given above if domain of PERSON_ID is a set of integer values from 1 to

1000 than a value outside this range will not be valid. Many other common domains may be age between 1 and 150. The domain can be definite by assigning a type or a format or a range to an attribute. For instance, a domain for a number 501 to 999 can be particular by having a 3-digit number format having a range of values between 501 and 999. Therefore, please note the domains can also be non-contiguous. For instance, the enrolment number of IGNOU has the last digit as the check digit, therefore the nine- digit enrolment numbers are non continuous.

Posted Date: 3/6/2013 5:16:18 AM | Location : United States







Related Discussions:- Domains, Assignment Help, Ask Question on Domains, Get Answer, Expert's Help, Domains Discussions

Write discussion on Domains
Your posts are moderated
Related Questions
Explain Record Based Logical Models? Record-Based logical Models: Also define data at the conceptual and view levels. Unlike object-oriented models, are used to state overall

Package classes and associations into modelsĀ  Programs are made of separate physical units which could be edited, imported, complied or otherwise manipulated. The careful part

Compare three clustering algorithms in Weka. For this comparison, you will need to use at least two different datasets. Run the algorithms on the datasets, and use the visual

Explain the Project-Join normal form A relation R is in PJNF along with respect to a set of functional dependencies D if for all join dependencies of the outline *(R 1 , R 2 ,

Indexed (Indexed Sequential) File Organisation It organises the file like a big dictionary, i.e., records are kept in order of the key but an index is stored which also allows

What are stand-alone procedures? Procedures that are not part of a package are called as stand-alone because they independently defined. A good example of a stand-alone procedu

Define single valued and multivalued attributes. Single valued attributes: attributes with a single value for a particular entity are known as single valued attributes. Mult

The File Based System File based systems are an early attempt to computerise the manual filing system. For example, a manual file can be set up to hold all the correspondence r

What is B-Tree? A B-tree eliminates the redundant storage of search-key values .It permits search key values to appear only once.

#queDefine a job scheduling strategy that will meet business requirement of reporting availability by 6am CST for the following cubes? Show the job scheduling dependencies in a pic