Question

I’m writing a general purpose function for feeding query string straight into a sproc. The algorithm is fairly basic – loop through query keys, use them as parameter names while the value are used as parameter values. So it looks like something like this:

ArrayList pars = new ArrayList();
SqlParameter p;
int tryInt;
for (int i = 0; i < req.QueryString.Count; i++) 
{
    key = req.QueryString.AllKeys[i];

    if (int.TryParse(req[key], out tryInt)) 
    {
        p = new SqlParameter("@" + key, SqlDbType.Int);
        p.Value = tryInt;
        pars.Add(p);
    }
}

This works fine so far, except that of course all query keys must match the parameters for the sproc, if they don’t I get an SQL exception saying something like

@someParameter is not a parameter for procedure some_sproc

But I need to be able to pass in variables in the query string that won’t be passed into the sproc, so I need a way to “ignore” them.

Is there a way to test whether a given stored procedure expects a certain parameter? So that I can do something along these lines

if (paramExists("@" + key, "some_sproc") && int.TryParse(req[key], out tryInt)) 
{
    p = new SqlParameter("@" + key, SqlDbType.Int);
    p.Value = tryInt;
    pars.Add(p);
}

Answer 1

you can interrogate the ANSI information_schema.parameters view, it returns all parameters with their position

SELECT parameter_name, ordinal_position FROM INFORMATION_SCHEMA.parameters
WHERE SPECIFIC_NAME = 'some_sproc'