Question

I’ve got a Coldfusion component, with a method in it called getColumnNames

This just queries a MySQL table, and returns the columnlist:

remote string function getColumnNames() {
    qProcessCars = new Query();
    qProcessCars.setDataSource('#APPLICATION.dsn#');
    qProcessCars.setSQL('SELECT * FROM sand_cars WHERE 1 LIMIT 1');
    qProcessCars = qProcessCars.Execute().getResult();

    return qProcessCars.columnlist;
}

If I access this remotely in the browser, with page.cfc?method=getColumnNames, then I get the expected list of columns back.

However, if I try to access this from inside another method within the component, I get an error

remote string function otherFunction() {
   ...
   sColumns = getColumnNames();
   ...
}

The error dump for the above code returns the message “The setSQL method was not found”.

So can anyone help me find out why it works as a remote call, but not when called from another method inside the same component.

Answer 1

Problem may be caused some kind of race conditions. If you make few calls which interfere, at some point qProcessCars may already be query result, so invoking method is not possible.

I would try to make the qProcessCars variable local scoped (var qProcessCars = new Query();
) and/or try to use another variable name for query results.

Next possible step is to enclose the query building/executing code into named lock.