Are there any advantages to use varchar over decimal for Price and Value

Question

I was arguing with my friend against his suggestion to store price, value and other similar informations in varchar.

My point of view are on the basis of

1. Calculations will become difficult as we need to cast back and forth.
2. Integrity of the data will be lost.
3. Poor performance of Indexes
4. Sorting and aggregate functions will also need casting

etc. etc.

But he was saying that in his previous employement everybody used to store such values in varchar, because the communication between DB and the APP will be very effective in this approach. (I still cant accept this)

Are there really some advantages in storing such values in varchar ?

Note : I'm not talking about columns like PhoneNo, IDs, ZIP Code, SSN etc. I know varchar is best suited for those. The columns are value based, and will for sure be involved in calculations some way or other.

Answer 1

None at all.

Try casting a values back and too and see how much data you lose.

DECLARE @foo TABLE (bar varchar(30))
INSERT @foo VALUES (11.2222222222)
INSERT @foo VALUES (22.3333333333)
INSERT @foo VALUES (33.1111111111)
SELECT CAST(CAST(bar AS float) AS varchar(30)) FROM @foo

I would also mention that his current employment does things differently... he isn't at his previous employment any more....