The Watcom Rule would imply "Intra-query parallelism is not used for connections with priority set to Background"... is that true?

The Help for the old background_priority option [deprecated] says "Intra-query parallelism is not used for connections with background_priority set to On".

However, the Help for the new priority option makes no such claim for SET TEMPORARY OPTION priority = 'Background'.

asked 07 Oct '18, 15:00

Breck%20Carter's gravatar image

Breck Carter
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accept rate: 20%

edited 15 Oct '18, 07:03


I have justed noted that the docs do tell about that, I have not checked reality:)

From the v17 "Parallelism in queries" topic:

Following is a list of circumstances in which a query cannot take advantage of parallelism, either at optimization or execution time:
* the server computer does not have multiple processors
* [...]
* the priority option is set to background

Makes sense, particularly as the deprecated Background_priority option is implemented as setting the priority option to 'Background'...

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answered 15 Oct '18, 08:02

Volker%20Barth's gravatar image

Volker Barth
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accept rate: 34%

edited 15 Oct '18, 08:03

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question asked: 07 Oct '18, 15:00

question was seen: 1,359 times

last updated: 15 Oct '18, 08:03