Attempting to do a join with 3 cores

[rhys J]

I was hoping to be able to do a join with 3 cores.

I found this page that seemed to indicate it's possible?

https://stackoverflow.com/questions/52380302/solr-how-to-join-three-cores

Here's my query:

http://localhost:8983/solr/dbtrphon/select?indent=on&rows=1000&sort=score
desc, id desc&q=(phone:*Meredith* OR descr:*Meredith*){!join from=debtor_id
to=debt_id fromIndex=debt}*&fq={!join from=debtor_id to=debtor_id
fromIndex=dbtr }(ssn1:12 OR ssn1:33) AND (assign_id:584 OR
assign_id:583)&cursorMark=*

{
  "responseHeader":{
    "status":400,
    "QTime":14,
    "params":{
      "q":"(phone:*Meredith* OR descr:*Meredith*){!join from=debtor_id
to=debt_id fromIndex=debt}*",
      "indent":"on",
      "cursorMark":"*",
      "sort":"score desc, id desc",
      "fq":"{!join from=debtor_id to=debtor_id fromIndex=dbtr
}(ssn1:12 OR ssn1:33) AND (assign_id:584 OR assign_id:583)",
      "rows":"1000"}},
  "error":{
    "metadata":[
      "error-class","org.apache.solr.common.SolrException",
      "root-error-class","org.apache.solr.common.SolrException"],
    "msg":"undefined field: \"debtor_id\"",
    "code":400}}


The schema for dbtrphon has debtor_id, the schema for debt has debt_id, and
the schema for dbtr has debtor_id. These fields all should be able to join,
but I get this error.

I've tried substituting debt_id for the debtor_id in the second join, but I
get the same error 'undefined field 'debt_id'.

I am unsure what I'm missing?

Thanks,

Rhys