On Wed, Apr 20, 2011 at 5:23 AM, Gan, Xiyun <[email protected]> wrote: > when use scan feature, i would fetch 1 row every time inside iterator, what > if the column qualifier reach millions entries. how do you loop through > that, and will there be a cache issue? >
You do in-row scan. You set an upper bound on how many columns to return on each next invocation [1.]. In this way you can iterate through a large row incrementally. Regards cache, you can set whether or not your scan goes via cache on the Scan object [2.]. St.Ack 1. http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/Scan.html#setBatch(int) 2. http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/Scan.html#setCacheBlocks(boolean)
