We have an item which contains account information as attributes e.g, account number, acct name, itemid, date etc. Is it possible to add multiple values to an attribute? If yes, how? Specifically, I would like to add multiple account numbers to an account name.
Your system wouldn't be even in Normal Form 0 if you would store multiple values in one filed.
Redesign your datamodel.
(with no way to store or retrieve multiple values into/from one INTEGER field. You would have to rely on a CHAR or VARCHAR field to store multiple values, you would also have to convert the number to and from a string to store or retrieve the value, how would you access the third value, .... a real nightmare)
with primary key (ID)
with primary key (ID_account_item, nr_account)
and foreign key (ID_account_item) that references account_item (ID)
For each account number you want to store, you just add one account_item_accNr record that references to the correct account_item record.
Going from your problem to this solution is a basic datamodelling skill. I'd recommend reading a good book about datamodelling or taking a course. It's not that hard to learn, but you really should master it before proceeding.
You should really have a good grab about normalising tables before doing anything in a production environment. Otherwise you will hit the wall and you will hit it hard. A normalised datamodel is easy(er) to expand, modify, update, query, ... , anything else will make it LOTS and lots harder.
With kind regards . . . . . SQL Server 2000/2005/2012
Grabel's Law: 2 is not equal to 3 -- not even for very large values of 2. Pat Phelan's Law: 2 very definitely CAN equal 3 -- in at least two programming languages