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From "Heather, James (ELS)" <>
Subject Re: querying time for Apache Phoenix
Date Wed, 27 Jul 2016 15:12:11 GMT
On Tue, 2016-07-26 at 08:39 -0700, James Taylor wrote:
- if you're querying for a single row, use the serial and small hints like this: /*+ SERIAL

Quoting from the language reference:

Generally, if the query is a point lookup or returns data that is likely in a single data
block (64 KB by default), performance may improve when using this hint.

Can you explain what's meant by "in a single data block"? Do you mean that the result is located
on a single region server, and in a single HDFS block on that region server?

In other words, if we're retrieving data from a single table, then it ought to be a small
number of rows with fairly closely located primary keys?



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