dynamo-query.js

var filter = { indexName: 'user_id-item_id-index', indexHashKey: 'user_id'};
var hash = 'secondary-index-hash-value';
	
ddb.query('table', hash, filter, function(err, res, cap) {
	console.log(res);
});
	
//DynamoDB ddb.js Update
//Remove Old HashKey
// data.HashKeyValue = scToDDB(hash)
if(options.indexHashKey){
	data.KeyConditionExpression = options.indexHashKey + " = :secondary_key";
	data.ExpressionAttributeValues = {
		":secondary_key": scToDDB(hash)
	};
}else{
	//ToDo: Change to Key
	data.HashKeyValue = scToDDB(hash)
}
//You have to upgrade to a newer version of Dynamo
//I'm using DynamoDB_20120810 for this example
//Upgrading Dynamo will break the HashKeyElement of this driver
//Around line 874 in ddb.js
'X-amz-target': 'DynamoDB_20120810.' + op,
'x-amz-target'         + ':' + 'DynamoDB_20120810.' + op + '\n') + '\n' +

HashKeyFix.js

// You have to explicitly define your hash and range properties for new versions of Dyanmo
// http://stackoverflow.com/a/16618235/1748015
var key = {_id: id, user_id: userId};

ddb.get('purchase', key, function(err, res, cap) { });

getItem = function(table, key, options, cb) {
    var data = {};
    try {
      data.TableName = table;
    //   Remove: HashKeyElement Deprecated
    //   var key = { "HashKeyElement": hash };
    //   if(typeof range !== 'undefined' &&
    //      range !== null)  {
    //     key.RangeKeyElement = range;
    //   }
      data.Key = objToDDB(key);