Stored procedure parameter data type that allows alphanumeric values

Question

I have a stored procedure for SQL 2000 that has an input parameter with a data type of varchar(17) to handle a vehicle identifier (VIN) that is alphanumeric. However, whenever I enter a value for the parameter when executing that has a numerical digit in it, it gives me an error. It appears to only accept alphabetic characters. What am I doing wrong here?

Answer 1

Based on comments, there is a subtle "feature" of SQL Server that allows letters a-z to be used as stored proc parameters without delimiters. It's been there forever (since 6.5 at least)

I'm not sure of the full rules, but it's demonstrated in MSDN (rename SQL Server etc): there are no delimiters around the "local" parameter. And I just found this KB article on it

In this case, it could be starting with a number that breaks. I assume it works for a contained number (but as I said I'm not sure of the full rules).

Edit: confirmed by Martin as "breaks with leading number", OK for "containing number"