SQL Error: Argument data type date is invalid for argument 2 of dateadd function

You new to cast the complete column as an integer before you can use the dateadd function. That means the following code: ,dateadd(d, CONVERT(date, CASE WHEN fda.[Column1] != 0 THEN fda.[Column1] WHEN fda.[Column2] != 0 THEN bfda.[Column1] ELSE fda.[Column3] END ,114), CONVERT(date, fda.[Column3], 114)) AS [tdate] needs to be changed to the code below. Note the convert becomes cast.   …