Why Doesnt This Work?

i am new at T-SQL and am trying to delete entries in a column that are not integers. i have the following code. why does it not work.

T-SQL

select invoicenumber from [control register] where convert(int, invoicenumber) like '%'
if @@error > 0
begin
delete from [control register] where invoicenumber = invoicenumber
end
go

gives me the error in Query analyser:

Server: Msg 245, Level 16, State 1, Line 1
Syntax error converting the nvarchar value '10-3-05' to a column of data type int.

@@error is supposed to pick up the error. why is it not.

please could you reply urgently at chris@captivedesign.co.za

thanks in advance



Chris Morton