There can be any # candidate keys but only one primary key in a table.. every candidate key can give u unique row in that table.... deciding which key should be the primary depends on some parameters like .. --length of the key .. --# of attributes in that key .. --frequency of using that key for u'r queries ..etc ..
On Sun, Sep 4, 2011 at 2:47 AM, sarath prasath <[email protected]>wrote: > what is the difference in this.. > we have a table which has one primary key and one unique key with not > null constraint.. > so r they equal...???? > > -- > You received this message because you are subscribed to the Google Groups > "Algorithm Geeks" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/algogeeks?hl=en. > > -- **Please do not print this e-mail until urgent requirement. Go Green!! Save Papers <=> Save Trees *BharatKumar Bagana* **http://www.google.com/profiles/bagana.bharatkumar<http://www.google.com/profiles/bagana.bharatkumar> * Mobile +91 8056127652* <[email protected]> -- You received this message because you are subscribed to the Google Groups "Algorithm Geeks" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en.
