SQL Update to flip the sign of a value?

Question

Someone entered a ton of numerical data into a table with a backslash.

Is there a clean way to flip a character in a numeric column using an SQL statement?

Answer 1

update my_table
  set amount = -amount
  where <whatever>

Answer 2

UPDATE [table] SET [column]=([column]*(-1))

You can add the sentence WHEREneeded to limit which lines you flip characters to.

Answer 3

.

update table set column = -column;

Answer 4

UPDATE MyTable
SET amount = -amount
WHERE amount = ABS(amount)

= ABS (), . , .