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any optimizer HINTs in Vertica ?

  • March 14, 2014
  • 1 reply
  • 5 views

K_Krutiy
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In Oracle you can change behavior of query optimizer with HINTs.

Something like this

SELECT /*+ FIRST_ROWS(10) */ column_name from table_name


SELECT /*+ CHOOSE */ column_name from table_name

 

 

I know Vertica has /*+DIRECT*/ for COPY command, which makes system to bypass WOS and write directly to ROS.

 

What about HINTs for SELECT ?

Does it have any ?

 

Thanks

 

 



 

1 reply

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  • Participating Frequently
  • March 15, 2014
Hi,

I believe the only other documented hint (also known as directive) is the label hint as shown below.
SELECT /*+label(myselectquery)*/ COUNT(*) FROM t;
There are some other undocumented ones Technical Support may use temporarily for debugging optimizer issues.