Convert positive to negative and vice versa

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Tyson L. Price Mr or Mrs. 500 Points: 589 More actions · Answer 1

I don't know about a function but just multiply by -1.

For example:

update InvoiceDtl set UnitPrice = UnitPrice * -1

NadJ Ten Centuries Points: 1031 More actions · Answer 2

Ten Centuries

Points: 1031

December 10, 2004 at 6:38 am

That'll work. ta

Ninja's_RGR'us SSC Guru Points: 294069 More actions · Answer 3

Actually if you only want ONLY positive values you'd be better off doing something like this :

Select ABS(MyCol) from dbo.MyTable

Sureshkumar Ramakrishnan Ten Centuries Points: 1200 More actions · Answer 4

I have used th case statement to do reverse the values present in the Table

select

case

when MyCol>0 then 0-MyCol

else

abs(MyCol)

end

from dbo.MyTable

Kindest Regards,

Sureshkumar Ramakrishnan

hoo-t SSChampion Points: 12713 More actions · Answer 5

Why????

As Tyson said, just multiply by -1.

positive values become negative ( 1 * -1 = -1).

negative values become positive (-1 * -1 = 1).

Thats what the original request was for!

No need for conditional logic, and abs() only provides the absolute value which is always positive, not what was requested.

Steve

Razvan Socol SSCarpal Tunnel Points: 4811 More actions · Answer 6

I can't believe that I see this question for the second time. I feel obligated to quote the response I wrote some time ago, in another group:

Well, this is a complicated question and it deserves a complicated answer

Let's create a table with test data first:

CREATE TABLE Numbers (X int)

INSERT INTO Numbers VALUES (-7)

INSERT INTO Numbers VALUES (0)

INSERT INTO Numbers VALUES (20)

I can think of a couple of ways to solve the problem:

SELECT X, CONVERT(int, CONVERT(varbinary(4),0x100000000 - CONVERT(bigint,X))) as N FROM Numbers

SELECT X, CASE WHEN SIGN(X)<0 THEN SIGN(X)*X ELSE (SIGN(X)-2 )*X END as N FROM Numbers

But how about the obvious way:

SELECT X, -X as N FROM Numbers

Razvan