Re: working around JSONB's lack of stats?

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От Peter Geoghegan
Тема Re: working around JSONB's lack of stats?
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Msg-id CAEYLb_VvYFj4WO4nmHHiz_JP_0qoaJ0mCejLews3oNajDr6vkg@mail.gmail.com
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Ответ на Re: working around JSONB's lack of stats?  (Josh Berkus <josh@agliodbs.com>)
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On Wed, Jan 28, 2015 at 3:03 PM, Josh Berkus <josh@agliodbs.com> wrote:
> We already have most_common_elem (MCE) for arrays and tsearch.  What if
> we put JSONB's most common top-level keys (or array elements, depending)
> in the MCE array?  Then we could still apply a simple rule for any path
> criteria below the top-level keys, say assuming that any sub-key
> criteria would match 10% of the time.  While it wouldn't be perfect, it
> would be better than what we have now.

Well, the "top-level keys" would still be gathered for expression
indexes. So yeah, maybe it would work alright for arrays of "tags",
and things like that. I tend to think that that's a common enough
use-case.

--
Regards,
Peter Geoghegan


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