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 SMALL */

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?

James

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