anchor.diff:  `q= *+title:join* +{!parent which="*content_type:parentDocument*"}comments:SolrCloud`
   ====
   
  -=== Scoring with the Block Join Parent Query Parser
  +==== Filtering and Tagging
  +
  +The `{!parent}` query supports `filters` and `excludeTags` local parameters like the following:
  +
  +[source,text]
  +{!parent which=<allParents> filters=$childfq excludeTags=certain}<someChildren>&
  +childfq=COLOR:Red&
  +childfq=SIZE:XL&
  +childfq={!tag=certain}PRINT:Hatched
  +
  +This is equivalent to:
  +
  +[source,text]
  +{!parent which=<allParents>}+<someChildren> +COLOR:Red +SIZE:XL
  +
  +Notice the "$" syntax in `filters` for referencing queries. Comma-separated tags in `excludeTags` allow excluding certain queries by tagging. Overall the idea is similar to <<faceting.adoc#tagging-and-excluding-filters, excluding fq in facets>>. Note that filtering is applied to the subordinate clause (`<someChildren>`) first, and the intersection result is joined to the parents.
  +
  +==== Scoring with the Block Join Parent Query Parser
   
   You can optionally use the `score` local parameter to return scores of the subordinate query. The values to use for this parameter define the type of aggregation, which are `avg` (average), `max` (maximum), `min` (minimum), `total (sum)`. Implicit default is `none` which returns `0.0`.
  +
  +==== All Parents Syntax
  +
  +When subordinate clause (`<someChildren>`) is omitted, it's parsed as a _segmented_ and _cached_ filter for all parent documents, or more precisely `q={!parent which=<allParents>}` is equivalent to `q=<allParents>`.
   
   == Boolean Query Parser
   
  
positive.code: ----
  
  This example creates a phrase query with "foo" followed by "bar" (assuming the analyzer for `myfield` is a text field with an analyzer that splits on whitespace and lowercase terms). This is generally equivalent to the Lucene query parser expression `myfield:"Foo Bar"`.
  
  == Function Query Parser
  
  
negative.code: 
  == Block Join Query Parsers
  
  There are two query parsers that support block joins. These parsers allow indexing and searching for relational content that has been <<uploading-data-with-index-handlers.adoc#uploading-data-with-index-handlers,indexed as nested documents>>.
  
  The example usage of the query parsers below assumes these two documents and each of their child documents have been indexed:
  
  