Elasticsearch: what sample document would look like for this mapping?

Question

I am new to Elasticsearch. I was given this mapping document:

{
    "book": {
        "properties": {
            "title": {
                "properties": {
                    "de": {
                        "type": "string",
                        "fields": {
                            "default": {
                                "type": "string",
                                "analyzer": "de_analyzer"
                            }
                        }
                    },
                    "fr": {
                        "type": "string",
                        "fields": {
                            "default": {
                                "type": "string",
                                "analyzer": "fr_analyzer"
                            }
                        }
                    }
                }
            }
        }
    }
}

I am wondering what a sample document conforming to this mapping would like so that I can generate right json string.

Thanks and regards.

Answer 1

Well, I'm way slow here, but, as dark_shadow points out, this looks like a convoluted attempt at exposing multiple analyzers for a field (formerly known as multi-field mapping). I've written up an example of mapping this in two ways: giving title two properties, fr and de, for which explicit strings need to be provided in each document, and just having a single title property, with fr and de analyzer 'fields'. Note that I replaced the name analyzers with "standard" to keep me from having to load those analyzers locally.

The difference between these is apparent. In example one, you have the ability to provide the translated titles on each book, with the index/search analyzer appropriate to the language being use on the respective properties.

In example two, you are providing a single title string, which will be indexed using both analyzers, and then you can choose the analyser to search by in your query.

#!/bin/sh
echo "--- delete index"
curl -X DELETE 'http://localhost:9200/so_multi_map/'
echo "--- create index and put mapping into place"
curl -XPUT http://localhost:9200/so_multi_map/?pretty -d '{
    "mappings": {
        "example_one": {
            "properties": {
                "title": {
                    "properties": {
                        "de": {
                            "type": "string",
                            "analyzer": "standard"
                        },
                        "fr": {
                            "type": "string",
                            "analyzer": "standard"
                        }
                    }
                }
            }
        },
        "example_two": {
            "properties": {
                "title": {
                    "type": "string",
                    "fields": {
                        "de": {
                            "type": "string",
                            "analyzer": "standard"
                        },
                        "fr": {
                            "type": "string",
                            "analyzer": "standard"
                        }
                    }
                }
            }
        }
    },
    "settings" : {
        "number_of_shards" : 1,
        "number_of_replicas" : 0
    }
}'

echo "--- index a book by example_one by POSTing"
curl -XPOST http://localhost:9200/so_multi_map/example_one -d '{
    "title": {
        "de": "Auf der Suche nach der verlorenen Zeit",
        "fr": "À la recherche du temps perdu"
    }
}'
echo "--- index a book by example_two by POSTing"
curl -XPOST http://localhost:9200/so_multi_map/example_two -d '{
    "title": "À la recherche du temps perdu"
}'
echo "\n --- flush indices"
curl -XPOST 'http://localhost:9200/_flush'
echo "--- show the books"
curl -XGET http://localhost:9200/so_multi_map/_search?pretty -d '
{
    "query": {
        "match_all": {}
    }
}'
echo "--- how to query just the fr title in example one:"
curl -XGET http://localhost:9200/so_multi_map/example_one/_search?pretty -d '
{
    "query": {
        "match": {
            "title.fr": "recherche"
        }
    }
}'
echo "--- how to query just the fr title in example two:"
curl -XGET http://localhost:9200/so_multi_map/example_two/_search?pretty -d '
{
    "query": {
        "match": {
            "title.fr": "recherche"
        }
    }
}'

Answer 2

It should look something similar to:

{
    "book": {
        "title": {
            "de": "somestring",
            "fr": "somestring"
        }
    }
}

For more information read this.

This is how your json will look like. I see you are confused by:

                   "fr": {
                        "type": "string",
                        "fields": {
                            "fr": {
                                "type": "string",
                                "analyzer": "fr_analyzer"
                            }
                        }
                    }

Actually this is used for indexing a single field in multiple ways. Effective you are telling elasticsearch that you want same field to index in two different ways. In your case I'm not getting why you are using same name "fr" and "de" for indexing multi-fields. If you will use same name, ES will index it only as a single field. So, in your case doing like this is a similar thing:

            "fr": {
                "type": "string",
                "analyzer": "fr_analyzer"
             }

For more information go through these links: http://www.elasticsearch.org/guide/en/elasticsearch/guide/current/most-fields.html http://www.elasticsearch.org/guide/en/elasticsearch/guide/current/multi-fields.html

Hope this helps.