ctargett commented on a change in pull request #113:
URL: https://github.com/apache/solr/pull/113#discussion_r626079125
##########
File path: solr/solr-ref-guide/src/common-query-parameters.adoc
##########
@@ -278,9 +278,12 @@ If you do not define the `wt` parameter in your queries,
JSON will be returned a
Solr caches the results of all queries and filter queries by default. To
disable result caching, set the `cache=false` parameter.
-You can also use the `cost` option to control the order in which non-cached
filter queries are evaluated. This allows you to order less expensive
non-cached filters before expensive non-cached filters.
+You can also use the `cost` option to provide a hint as to the order in which
non-cached filter queries are evaluated.
+This allows you to order less expensive non-cached filters before expensive
non-cached filters.
+At the Lucene layer, this maps to `TwoPhaseIterator.matchCost` if the query
has a TPI.
-For very high cost filters, if `cache=false` and `cost>=100` and the query
implements the `PostFilter` interface, a Collector will be requested from that
query and used to filter documents after they have matched the main query and
all other filter queries. There can be multiple post filters; they are also
ordered by cost.
+*Post Filters*: For very high cost filters, if `cache=false` _and_
`cost>=100`, _and_ the query implements the `PostFilter` interface, a Collector
will be requested from that query and used to filter documents after they have
matched the main query and all other filter queries.
Review comment:
> These two parameters would best be documented beneath "fq" (filter
query) documentation and maybe referenced from another page that defines the
caches if such exists.
I agree. I think it would be in scope of this PR to move it? Or not, up to
you.
> Outside of this paragraph, the only other instance of "PostFilter" I see
is on the spatial page.
The docs on collapse mention that the CollapsingQParser is a post filter, as
a way of introducing it (in italics even), but again does not define what it is
or provide any context for why that matters. For most users that means
absolutely nothing when they don't know what a post filter is to begin with. Of
course, dealing with that is out of scope for this PR, but it is another place
where the term is just dropped in without any ability for anyone to learn what
it is.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
[email protected]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
