Elasticsearch – sorting on string types with more than one value per doc, or more than one token per field
We were experiencing problems with sorting results with a recent version of elasticsearch.
Typical sort on name field (consisting of both first and last names) was coming back with exception:
“Can’t sort on string types with more than one value per doc, or more than one token per field”
Other users also experienced the problem:
http://elasticsearch-users.115913.n3.nabble.com/Sorting-failing-in-latest-master-td967979.html
The solution was to add multi type mapping on the field. Initially the mapping was plain string:
curl -s -XGET 'es:9200/users/journalist/_mapping'
{
"journalist": {
"properties": {
"name": {
"type": "string"
}
}
}
}
and the search queries like below , were failing.
curl -s -XGET es:9200/users/journalist/_search -d '
{
"sort": [ { "name" : "asc" } ],
"fields": ["name"],
"query" : {
"query_string": {
"query": "harry",
"fields": [ "name" ]
}
}
}'
Following the documentation I’ve replaced the mapping on “name” field to be a composite of standard string type and not analyzed version of it:
curl -s -XPUT es:9200/users/journalist/_mapping -d '
{
"journalist" : {
"properties": {
"name" : {
"type": "multi_field",
"fields" : {
"name": {
"type" : "string"
},
"untouched" : {
"type": "string",
"index" : "not_analyzed"
}
}
}
}
}
}'
To verify:
curl -s -XGET 'es:9200/users/journalist/_mapping'
{
"journalist": {
"name": {
"fields": {
"name": {
"type": "string"
},
"untouched": {
"include_in_all": false,
"index": "not_analyzed",
"type": "string"
}
},
"type": "multi_field"
}
}
}
}
After reindexing and changing the sort query (note the “name.untouched” part), the search went fine.
curl -s -XGET es:9200/users/journalist/_search -d '
{
"sort": [ { "name.untouched" : "asc" } ],
"fields": ["name"],
"query" : {
"query_string": {
"query": "harry",
"fields": [ "name" ]
}
}
}'
).