(Posting anon b/c I don't have my pw saved on this browser.) Apologies, I don't know how many times I looked at your first example and it never clicked that you had them grouped by <data2>, which is indeed what I was going for. To clarify, <data2> is a client identifier, and I need to grab all log messages (<data1>) for each client , group them together by client (hence the hash of arrays with the client ID as key), and then sort each group of logs by time. I haven't tried to implement it yet, but it does indeed look like what I was trying to do. Thanks.