Hello,
given the following document structure (books as parent, libraries having these
books as children):
<update>
<add>
<doc>
<field name="doc_type_s">book</field>
<field name="id">1000</field>
<field name="title_t">Mr. Mercedes</field>
<field name="autor_t">Stephen King</field>
<doc>
<field name="doc_type_s">library</field>
<field name="id">1000/100</field>
<field name="acquisition_date_i">20160810</field>
<field name="city_t">Innsbruck</field>
</doc>
<doc>
<field name="doc_type_s">library</field>
<field name="id">1000/101</field>
<field name="acquisition_date_i">20180103</field>
<field name="city_t">Hall</field>
</doc>
</doc>
<doc>
<field name="doc_type_s">book</field>
<field name="id">1001</field>
<field name="title_t">Noah</field>
<field name="autor_t">Sebastian Fitzek</field>
<doc>
<field name="doc_type_s">library</field>
<field name="id">1001/100</field>
<field name="acquisition_date_i">20170810</field>
<field name="city_t">Innsbruck</field>
</doc>
</doc>
</add>
</update>
Now i want to get all books located in libraries in city "Innsbruck", sorted by
acquisition date descending.
In other words: i want to filter in the field city_i in the child documents,
but return only the parent document. And i want to sort by the field
acquisition_date_i in the child documents in descending order, newest first.
My first try:
-----
URL:
http://localhost:8983/solr/test1/select?q=title_t:*&fq={!parent%20which=doc_type_s:book}city_t:Innsbruck&sort={!parent%20which=doc_type_s:book%20score=max%20v=%27%2Bdoc_type_s:library%20%2B{!func}acquisition_date_i%27}%20desc
URL params decoded:
q=title_t:*
fq={!parent which=doc_type_s:book}city_t:Innsbruck
sort={!parent which=doc_type_s:book score=max v='+doc_type_s:library
+{!func}acquisition_date_i'} desc
Result:
{
"responseHeader":{
"status":0,
"QTime":4,
"params":{
"q":"title_t:*",
"fq":"{!parent which=doc_type_s:book}city_t:Innsbruck",
"sort":"{!parent which=doc_type_s:book score=max v='+doc_type_s:library
+{!func}acquisition_date_i'} desc"}},
"response":{"numFound":2,"start":0,"docs":[
{
"doc_type_s":"book",
"text":["book",
"Mr. Mercedes",
"Stephen King"],
"id":"1000",
"title_t":"Mr. Mercedes",
"title_t_fac":"Mr. Mercedes",
"autor_t":"Stephen King",
"autor_t_fac":"Stephen King",
"_version_":1591205521252155392},
{
"doc_type_s":"book",
"text":["book",
"Noah",
"Sebastian Fitzek"],
"id":"1001",
"title_t":"Noah",
"title_t_fac":"Noah",
"autor_t":"Sebastian Fitzek",
"autor_t_fac":"Sebastian Fitzek",
"_version_":1591205521256349696}]
}}
The result is wrong, because "Noah" should be before "Mr. Mercedes" in the
list. The reason is, i guess, because "Mr. Mercedes" has another child document
with a newer acquisition_date. But this child document is not in city
"Innsbruck" and should not influence the sorting.
So i tried to add the city-filter to the sort-parameter as well in my second
try:
-----
URL:
http://localhost:8983/solr/test1/select?q=title_t:*&fq={!parent%20which=doc_type_s:book}city_t:Innsbruck&sort={!parent%20which=doc_type_s:book%20score=max%20v=%27%2Bdoc_type_s:library%20%2Bcity_t:Innsbruck%20%2B{!func}acquisition_date_i%27}%20desc
URL params decoded:
q=title_t:*
fq={!parent which=doc_type_s:book}city_t:Innsbruck
sort={!parent which=doc_type_s:book score=max v='+doc_type_s:library
+city_t:Innsbruck +{!func}acquisition_date_i'} desc
(I added "+city_t:Innsbruck" to the sort param)
Result:
{
"responseHeader":{
"status":0,
"QTime":3,
"params":{
"q":"title_t:*",
"fq":"{!parent which=doc_type_s:book}city_t:Innsbruck",
"sort":"{!parent which=doc_type_s:book score=max v='+doc_type_s:library
+city_t:Innsbruck +{!func}acquisition_date_i'} desc"}},
"response":{"numFound":2,"start":0,"docs":[
{
"doc_type_s":"book",
"text":["book",
"Noah",
"Sebastian Fitzek"],
"id":"1001",
"title_t":"Noah",
"title_t_fac":"Noah",
"autor_t":"Sebastian Fitzek",
"autor_t_fac":"Sebastian Fitzek",
"_version_":1591205521256349696},
{
"doc_type_s":"book",
"text":["book",
"Mr. Mercedes",
"Stephen King"],
"id":"1000",
"title_t":"Mr. Mercedes",
"title_t_fac":"Mr. Mercedes",
"autor_t":"Stephen King",
"autor_t_fac":"Stephen King",
"_version_":1591205521252155392}]
}}
Now the sorting is correct.
My question:
Is there a way to achieve the same result without having add all filters to the
search-param?
In other words: is there a way to sort on a child field, but only in matching
child-documents?
Thanks for your help.
Florian
