Hi! Sorry for digging out this thread, but I am currently facing the same problem and decided to run MR job to transform my data before importing it.   However, I am unsure what the data output should look like for it to be understood by HBase. As far as I know, HBase saves everything as bytes anyway, but makes a difference for timestamps. So,say I want to queue Factory_ID:YYYMMDD:Order_ID:UID for my composite key. Should I output them with ":" as a separator. Or just one after another? Will HBase be able to use this information to shard the table into different regions?   Thanks in advance! ... View more