Multi-field Search with Array Using 'AND' Operator in elasticsearch - elasticsearch

Question

I want to query the values of a multi-value field as separate 'fields' in the same way I'm querying the other fields.
I have a data structure like so:
{
name: 'foo one',
alternate_name: 'bar two',
lay_name: 'baz three',
tags: ['stuff like', 'this that']
}
My query looks like this:
{
query:
query: stuff
type: 'best_fields',
fields: ['name', 'alternate_name', 'lay_name', 'tags'],
operator: 'and'
}
The 'type' and 'operator' work perfectly for the single value fields in only matching when the value contains my entire query. For example, querying 'foo two' doesn't return a match.
I'd like the tags field to behave the same way. Right now, querying 'stuff that' will return a match when it shouldn't because no fields or tag values contain both words in a single value. Is there a way to achieve this?
EDIT
Val's assessment was spot on. I've updated my mapping to the following (using elasticsearch-rails/elasticsearch-model):
mapping dynamic: false, include_in_all: true do
... other fields ...
indexes :tags, type: 'nested' do
indexes :tag, type: 'string', include_in_parent: true
end
end

Answer 1

Please show your mapping type, but I suspect your tags field is a simple string field like this:
{
"your_type" : {
"properties" : {
"tags" : {
"type" : "string"
}
}
}
}
In this case ES will "flatten" all your tags under the hood in the tags field at indexing time like this:
tags: "stuff", "like", "this", "that"
i.e. this is why you get results when querying "stuff that", because the tags field contains both words.
The way forward would be to make tags a nested object type, like this
{
"your_type" : {
"properties" : {
"tags" : {
"type" : "nested",
"properties": {
"tag" : {"type": "string" }
}
}
}
}
}
You'll need to reindex your data but at least querying for tags: "stuff that" will not return anything anymore. Your tag tokens will be "kept together" as you expect. Give it a try.