Is it bug or by design: if i group docs with option "&group.facet=true" then
facet counts are grouped and "represent" groups, including the fact that no
count can be larger than number of groups.
But when the docs have nested docs and i additionally fetch neested docs facet
with option "child.facet.field=some_field" then those facets are not grouped
(they still relate to parent docs but not to "superparent" groups).
Example:
4 parent documents, each with 2 nested documents; parent documents will be
grouped to 2 groups with 2 documents each.
<update>
<delete><query>*:*</query></delete>
<add>
<doc>
<field name="group_id_s">1</field>
<field name="id">11</field>
<field name="doc_type_s">parentDoc</field>
<field name="color_s">RED</field>
<doc>
<field name="id">111</field>
<field name="doc_type_s">nestedDoc</field>
<field name="size_s">L</field>
</doc>
<doc>
<field name="id">112</field>
<field name="doc_type_s">nestedDoc</field>
<field name="size_s">L</field>
</doc>
</doc>
<doc>
<field name="group_id_s">1</field>
<field name="id">12</field>
<field name="doc_type_s">parentDoc</field>
<field name="color_s">RED</field>
<doc>
<field name="id">121</field>
<field name="doc_type_s">nestedDoc</field>
<field name="size_s">L</field>
</doc>
<doc>
<field name="id">122</field>
<field name="doc_type_s">nestedDoc</field>
<field name="size_s">XL</field>
</doc>
</doc>
<doc>
<field name="group_id_s">2</field>
<field name="id">21</field>
<field name="doc_type_s">parentDoc</field>
<field name="color_s">RED</field>
<doc>
<field name="id">211</field>
<field name="doc_type_s">nestedDoc</field>
<field name="size_s">L</field>
</doc>
<doc>
<field name="id">212</field>
<field name="doc_type_s">nestedDoc</field>
<field name="size_s">XXL</field>
</doc>
</doc>
<doc>
<field name="group_id_s">2</field>
<field name="id">22</field>
<field name="doc_type_s">parentDoc</field>
<field name="color_s">BLUE</field>
<doc>
<field name="id">221</field>
<field name="doc_type_s">nestedDoc</field>
<field name="size_s">XL</field>
</doc>
<doc>
<field name="id">222</field>
<field name="doc_type_s">nestedDoc</field>
<field name="size_s">XXL</field>
</doc>
</doc>
</add>
</update>
Requests:
1. /bjqfacet?q={!parent
which=doc_type_s:parentDoc}doc_type_s:nestedDoc&child.facet.field=size_s
Returns 4 parent documents, nested facets reflect it: no count larger than 4
and for example size L count is only 3 since for the first parent doc it
appeared in both nested docs, so for this parent doc it counts for 1.
<lst name="size_s">
<int name="L">3</int>
<int name="XL">2</int>
<int name="XXL">2</int>
</lst>
2. /bjqfacet?q={!parent
which=doc_type_s:parentDoc}doc_type_s:nestedDoc&child.facet.field=size_s&facet=true&facet.field=color_s
Adding color facet:
<lst name="color_s">
<int name="RED">3</int>
<int name="BLUE">1</int>
</lst>
<lst name="size_s">
<int name="L">3</int>
<int name="XL">2</int>
<int name="XXL">2</int>
</lst>
3. /bjqfacet?q={!parent
which=doc_type_s:parentDoc}doc_type_s:nestedDoc&child.facet.field=size_s&group=true&group.field=group_id_s&group.facet=true&facet=true&facet.field=color_s
Adding grouping. Returns 2 groups.
Color facets are grouped here reflecting groups. In a similar way in 1st
request size facets changed to reflect parent documents, not nested documents.
But here, after grouping, size facet counts do not change: they still reflect
parent documents, not groups (for example size L count = 3 > number of groups =
2).
<lst name="color_s">
<int name="RED">2</int>
<int name="BLUE">1</int>
</lst>
<lst name="size_s">
<int name="L">3</int>
<int name="XL">2</int>
<int name="XXL">2</int>
</lst>
So is it bug or by design? If bug when it could be fixed?
And how it can be fixed locally? I guess when grouping happens info about
nested doc facets is already known and hence they can be grouped in a similar
way like usual parent doc fields?
