I am joining two tables by using only a key fields in two tables. (if this were straight hbase, I know I would code with some range scans) There are many billions of rows in each table. I am trying to understand the explain plan as I am having difficulties with query failures under various load testing scenarios. When used in sqlline, the query for which I am posting the plan can take 6-30 seconds.
Below is my explain plan. CLIENT 173251-CHUNK 87628582101 ROWS 53384270894992 BYTES PARALLEL 1-WAY ROUND ROBIN FULL SCAN OVER CLICKS SERVER FILTER BY FIRST KEY ONLY PARALLEL INNER-JOIN TABLE 0 (SKIP MERGE) CLIENT 5181-CHUNK 14470353216 ROWS 1562798147328 BYTES PARALLEL 256-WAY ROUND ROBIN SKIP SCAN ON 25600 KEYS OVER PRODUCT [0,'020lj7'] - [255,'z4l777'] SERVER FILTER BY FIRST KEY ONLY DYNAMIC SERVER FILTER BY CLICKS.SHA_KEY IN (PRODUCT.SHA_KEY) Question: Does " FULL SCAN " truly mean full scan? I do know that running the hbase map reduce RowCounter to perform a row count, which truly is a full scan, can take over 30 minutes. So I am very confused about - when is a FULL SCAN really a full scan? Thanks for any insight. ____________________________________________________________ Actress Maggie Q Shocks With Her Solution To Tummy Troubles ActivatedYou http://thirdpartyoffers.netzero.net/TGL3231/597a4efb256f54efb5d0cst02vuc