Check for Numeric Value using SQL Server 2000

Question

How can I know if a VARCHAR field's value can be successfully converted to an integer?

I want to do it massively to insert records from one table to another...

Answer 1

IsNumeric() function returns 1 for strings (varchars) which can be converted to a number and 0 for those that cannot..

Check out IsNumeric function

Answer 2

One issue whit IsNumeric() function is that You will get True and if number got decimal separator, What is totally right, But if someone as I need to check straight to numbers in varchar, without decimal symbols, (I got that when I needed to calculate CHECK digit on barcode) You can use castom made function like

create FUNCTION [dbo].[checkbarkod] 
(
    @ean_kod varchar(13)
)
RETURNS bit
AS
begin
    declare @duzina int
    declare @slovo char(1)
    declare @pozicija int
    declare @uredu bit
    set @duzina=len(@ean_kod) 
    while @duzina>0
     begin
      set @slovo=(substring(@ean_kod,@duzina,1))
      if  (@slovo not in('1','2','3','4','5','6','7','8','9','0'))
       begin
        set @uredu=convert(bit,0)
        break
       end
      else 
       begin
        set @uredu=convert(bit,1)
        set @duzina=@duzina-1
      end
     end
    RETURN @uredu
end