elasticsearch/elasticsearch — pull request #7858 by rmruano (2014-09-24 14:50:29+00:00)
Title: Update delete-by-query.asciidoc

Undocumented limitation. Support for both has_parent & has_child has been dropped by commit:
https://github.com/elasticsearch/elasticsearch/commit/17a5575757317962dab4c295bbfacbdb136cc61e