Sending result set back to client in node.js

I am having an issue getting the result set back to the client using Node.js. I am new to it and using it for a project but I am stuck and not sure why. Here's the situation: I have a webpage, a server, a request handler and a database interface. I am able to send data back and forth the client and server without any issue. The only time it doesn't work is when I try to send the result from my query back to the client.

function doSomething(response)
{
    var data = {
        'name': 'doSomething'
    };

    response.writeHead(200, {'Content-Type': 'text/html', 'Access-Control-Allow-Origin': '*'});     
    response.end(JSON.stringify(data));
}

This works fine as I can read the name from the object on the client side, but

function fetchAllIDs(response)
{
    dbInterface.fetchAllIDs(function(data) {
        // console.log(data) prints the correct information here        
        response.writeHead(200, {'Content-Type': 'text/html', 'Access-Control-Allow-Origin': '*'});     
        response.end(data);
        // console.log(data) from the client side is just blank
    });
}

I believe the issue is the way I handle my callback and response because without trying to use mysql the rest of my code works fine. Thanks!

EDIT: I removed a piece code that seems to confuse people. It was just to show that if I have the response code outside the callback then I am able to get any data back to the server. In my actual code, I do not have the two response statements together. I just can't get the rows from the fetchAllIDs function back to the client.