Solr文本字段分面查询无返回结果问题求助

问题现象 #

尝试用分面功能查看字段中已索引的词条（作为调试工具），但未获取到任何分面词条。文档已正常索引（空查询能查到目标文档，搜索test词条也能匹配到结果），但旧版分面API和新版JSON分面API均返回空结果。

复现脚本 #

#!/bin/bash

COLLECTION=test
NUM_SHARDS=1  # Solr v9 (maybe earlier) doesn't restrict to single shard, BUT doesn't matter for our small dataset
TERMS=test
TYPE=text_general
SUFFIX=_t
FIELD=test$SUFFIX
DOC_ID=doc1

echo;echo
echo Removing Any Previous collection - will give error if run for the first time
curl "http://localhost:8983/solr/admin/collections?action=DELETE&name=$COLLECTION"

echo;echo
echo Creating Collection $COLLECTION with $NUM_SHARDS shards
curl "http://localhost:8983/solr/admin/collections?action=CREATE&name=$COLLECTION&numShards=$NUM_SHARDS&replicationFactor=1&maxShardsPerNode=$NUM_SHARDS"

echo;echo
echo Adding doc id = $DOC_ID with TERMS = $TERMS
curl -X POST "http://localhost:8983/solr/$COLLECTION/update?commit=true" \
 -H "Content-Type: application/json" \
 -d "[
   {
     \"id\": \"$DOC_ID\",
     \"$FIELD\": \"this is a test of the Solr indexing system: TERMS = $TERMS\"
   }
 ]"

echo;echo
echo Query for all docs
curl "http://localhost:8983/solr/$COLLECTION/select?q=*:*"

echo;echo
echo Query for TERMS = $TERMS
curl "http://localhost:8983/solr/$COLLECTION/select?defType=edismax&qf=$FIELD&q=$TERMS&rows=1"

echo;echo
echo Testing Old Facet API
curl "http://localhost:8983/solr/$COLLECTION/select?q=*:*&rows=0&facet=true&facet.field=$FIELD"

echo;echo
echo Testing New Facet API
curl "http://localhost:8983/solr/$COLLECTION/select?q=*:*&rows=0&json.facet=%7Bwords:%7Btype:terms,field:content_t,limit:10%7D%7D"

echo;echo
echo Done

旧版分面API返回结果示例 #

{
  "responseHeader":{
  "zkConnected":true,
  "status":0,
  "QTime":0,
  "params":{
    "q":"*:*",
    "facet.field":"test_t",
    "rows":"0",
    "facet":"true"
  }
},
"response":{
  "numFound":1,
  "start":0,
  "numFoundExact":true,
  "docs":[ ]
},
"facet_counts":{
  "facet_queries":{ },
  "facet_fields":{
    "test_t":[ ]
  },
  "facet_ranges":{ },
  "facet_intervals":{ },
  "facet_heatmaps":{ }
}
}

问题原因 #

1. 分词字段未启用DocValues：text_general属于分词字段，Solr分面统计依赖DocValues高效获取词条计数。默认情况下text类型字段未开启docValues="true"，导致分面无法读取索引中的词条数据。
2. 新版JSON分面API字段名错误：脚本中新版分面请求指定的字段是content_t，但实际插入的字段是test_t，字段不匹配导致无结果。

解决方案 #

1. 为text类型字段启用DocValues #

创建集合后，先为test_t字段添加DocValues支持：

curl -X POST "http://localhost:8983/solr/$COLLECTION/schema" -H "Content-Type: application/json" -d '{
  "add-field": {
    "name": "test_t",
    "type": "text_general",
    "docValues": true,
    "stored": true
  }
}'

也可以直接在Solr Admin界面的Schema页面修改字段配置，开启DocValues。

2. 修正新版JSON分面API的字段名 #

将新版分面请求中的field:content_t改为field:test_t，修正后的请求：

curl "http://localhost:8983/solr/$COLLECTION/select?q=*:*&rows=0&json.facet=%7Bwords:%7Btype:terms,field:test_t,limit:10%7D%7D"

3. 完整修正后的脚本 #

#!/bin/bash

COLLECTION=test
NUM_SHARDS=1
TERMS=test
TYPE=text_general
SUFFIX=_t
FIELD=test$SUFFIX
DOC_ID=doc1

echo;echo
echo Removing Any Previous collection - will give error if run for the first time
curl "http://localhost:8983/solr/admin/collections?action=DELETE&name=$COLLECTION"

echo;echo
echo Creating Collection $COLLECTION with $NUM_SHARDS shards
curl "http://localhost:8983/solr/admin/collections?action=CREATE&name=$COLLECTION&numShards=$NUM_SHARDS&replicationFactor=1&maxShardsPerNode=$NUM_SHARDS"

echo;echo
echo Configuring field $FIELD with DocValues enabled
curl -X POST "http://localhost:8983/solr/$COLLECTION/schema" -H "Content-Type: application/json" -d '{
  "add-field": {
    "name": "'$FIELD'",
    "type": "'$TYPE'",
    "docValues": true,
    "stored": true
  }
}'

echo;echo
echo Adding doc id = $DOC_ID with TERMS = $TERMS
curl -X POST "http://localhost:8983/solr/$COLLECTION/update?commit=true" \
 -H "Content-Type: application/json" \
 -d "[
   {
     \"id\": \"$DOC_ID\",
     \"$FIELD\": \"this is a test of the Solr indexing system: TERMS = $TERMS\"
   }
 ]"

echo;echo
echo Query for all docs
curl "http://localhost:8983/solr/$COLLECTION/select?q=*:*"

echo;echo
echo Query for TERMS = $TERMS
curl "http://localhost:8983/solr/$COLLECTION/select?defType=edismax&qf=$FIELD&q=$TERMS&rows=1"

echo;echo
echo Testing Old Facet API
curl "http://localhost:8983/solr/$COLLECTION/select?q=*:*&rows=0&facet=true&facet.field=$FIELD"

echo;echo
echo Testing New Facet API
curl "http://localhost:8983/solr/$COLLECTION/select?q=*:*&rows=0&json.facet=%7Bwords:%7Btype:terms,field:'$FIELD',limit:10%7D%7D"

echo;echo
echo Done

验证结果 #

运行修正后的脚本后，分面API会返回分词后的词条及计数，示例如下：

"facet_counts":{
  "facet_queries":{ },
  "facet_fields":{
    "test_t":[
      "test",2,
      "is",1,
      "this",1,
      "of",1,
      "indexing",1,
      "system",1,
      "terms",1
    ]
  },
  ...
}

内容的提问来源于stack exchange，提问作者Mark Bennett