can primary key be modified or changed? as far as i have seen there were no options to change or modify. it can only be dropped and added! if its true please tell me why it cant be modified or changed?
thanks n cheers!

Primary cannot be modified due to this will be refrence to many other table
You have to make lots of modification

if u want to drop the primary key u have to drop the foreign key constraint which references with primary key and then drop the primary key constriant

actually, that's not true

do a search for ON UPDATE CASCADE

I understood for changes in primary key column name or data type
which can also be change by droping and recreating reference key

From the data perspective that's true, but I think the question was intended from the schema perspective. Thats a different problem.

-PatP