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Himanshu Vashishtha commented on HBASE-1512: -------------------------------------------- Hello Andrew, Can you please tell where should I start digging and changing stuff to make it work. I have seen your code under the patch 2001, and would like to work on coprocessors, starting from this jira. Will fetching codebase from github (as mentioned there) will give me the right code base...seems things have changed since then. What is the right way to do this. Thanks, Himanshu > Coprocessors: Support aggregate functions > ----------------------------------------- > > Key: HBASE-1512 > URL: https://issues.apache.org/jira/browse/HBASE-1512 > Project: HBase > Issue Type: Sub-task > Reporter: stack > > Chatting with jgray and holstad at the kitchen table about counts, sums, and > other aggregating facility, facility generally where you want to calculate > some meta info on your table, it seems like it wouldn't be too hard making a > filter type that could run a function server-side and return the result ONLY > of the aggregation or whatever. > For example, say you just want to count rows, currently you scan, server > returns all data to client and count is done by client counting up row keys. > A bunch of time and resources have been wasted returning data that we're not > interested in. With this new filter type, the counting would be done > server-side and then it would make up a new result that was the count only > (kinda like mysql when you ask it to count, it returns a 'table' with a count > column whose value is count of rows). We could have it so the count was > just done per region and return that. Or we could maybe make a small change > in scanner too so that it aggregated the per-region counts. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.