On Wed, Jun 6, 2012 at 7:35 AM, S Ahmed <[email protected]> wrote: > When hbase lookups a cell in a column family, how does it perform the > lookup? Is there an index on the file, or is it ordered?
Ordered. Has an "index" of sorted keys to offsets. > What algorithm is used? > Does it load the entire column family file in memory, or scan it? > Scan (file index is kept in LRU). > I know the actual rows are ordered lexically, is it the same for column > family qualifiers? > Yes. > If someone could also point me to the relevant files that would be great. Start with "9.7.5 Store" in http://hbase.apache.org/book/regions.arch.html It has pointers into source. St.Ack
