Change dynamic field title in solr select query

Question

I am using solr to retrieve results from a cassandra table.

Table structure:

CREATE TABLE mytable (
  field1 uuid,
  field2 text ,
  bfield blob,
  custmdata_<text, text>,
  PRIMARY KEY (field1)
);

Table content

INSERT INTO mytable  VALUES ( 62c36092-82a1-3a00-93d1-46196ee77204,"test1", { 'custmdata_data1'  : 'data1value', 'custmdata_data2' : 'data2value' });
INSERT INTO mytable  VALUES ( e26690db-dd54-4b61-b002-d3c07125f359,"test2", { 'custmdata_data5'  : 'data5value', 'custmdata_data1' : 'mydata1value' });

I am able to retrieve the results using solr query.

{
  "responseHeader": {
    "status": 0,
    "QTime": 1
  },
  "response": {
    "numFound": 2,
    "start": 0,
    "docs": [
      {
        "field1": "62c36092-82a1-3a00-93d1-46196ee77204",
        "field2": "test1",
         "custmdata_data1":"data1value",
         "custmdata_data2" : "data2value"
      },
      {
        "field1": "e26690db-dd54-4b61-b002-d3c07125f359",
        "field2": "test2",
         "custmdata_data5":"data5value",
         "custmdata_data1" : "mydata1value"
      }
    ]
  }
}

Is there any way to specify the field name in result so that I can retrieve the dynamic fields without having the field name prefix? I need result like this:

{
      "responseHeader": {
        "status": 0,
        "QTime": 1
      },
      "response": {
        "numFound": 2,
        "start": 0,
        "docs": [
          {
            "field1": "62c36092-82a1-3a00-93d1-46196ee77204",
            "field2": "test1",
             "data1":"data1value",
             "data2" : "data2value"
          },
          {
            "field1": "e26690db-dd54-4b61-b002-d3c07125f359",
            "field2": "test2",
             "data5":"data5value",
             "data1" : "mydata1value"
          }
        ]
      }
    }

Update: From datastax documentaion, I found that,

Avoid or limit the use of dynamic fields. Lucene allocates memory for each unique field (column) name, so if you have a row with columns A, B, C, and another row with B, D, E, Lucene allocates 5 chunks of memory. For millions of rows, the heap is unwieldy.

So is there a better way to achieve dynamic field based filtering in Solr? What I need is to filter against custom fields that may vary for each insert.

Bereng Bereng · Accepted Answer · 2016-07-25T08:45:55

Instead of calling your dyn field custmdata_ call it data and that should get rid of the bit you don't want.

Otherwise removing the dyn field prepended label is not supported but you can rename returned fields with fl: https://wiki.apache.org/solr/CommonQueryParameters#Field_alias

If you're worried about having too many dyn fields, try to workaround it with some C* collection type if you scenario lends itself to that.

Change dynamic field title in solr select query

1 Answers