Can we fing clusters of following data?
Id P1 P2
x 5.6 4.5
x 1.6 4.5
y 5.6 4.5
having 2 clusters?
I think original poster is referring to "clusters" on its data mining meaning, as in "data clustering" as opposed to "clustered/non-clustered indexes".
Having said that, PKs are created to enforce uniqueness on a column or combination of columns, more related to referential integrity than to data mining - you can do "data clustering" in an indexless, PKless table.
Pablo (Paul) Berzukov
Author of Understanding Database Administration
available at Amazon and other bookstores.Disclaimer: Advice is provided to the best of my knowledge but no implicit or explicit warranties are provided. Since the advisor explicitly encourages testing any and all suggestions on a test non-production environment advisor should not held liable or responsible for any actions taken based on the given advice.