How to search for a term and match a boolean condition

Question

I've had good success getting results for searches using the below syntax, but I'm having trouble adding a boolean condition.

http://localhost:9200/index_name/type_name/_search?q=test

My documents look like:

{
    "isbn":"9780307414922",
    "name":"Dark of the Night",
    "adult":false
}

Here's my best guess as to how to achieve what I'm trying to do.

{
    "query_string": {
        "default_field": "_all",
         "query": "test"
    },
    "from": 0,
    "size": 20,
    "terms": {
        "adult": true
    }
}

However this results in "Parse Failure [No parser for element [query_string]]]; }]"

I'm using elastic search 0.20.5.

How can I match documents containing a search term the way "?q=test" does and filter by the document's adult property?

Thanks in advance.

Answer 1

Your adult == true clause has to be part of the query - you can't pass in a term clause as a top level parameter to search.

So you could add it to the query as a query clause, in which case you need to join both query clauses using a bool query, as follows:

curl -XGET 'http://127.0.0.1:9200/_all/_search?pretty=1'  -d '
{
   "query" : {
      "bool" : {
         "must" : [
            {
               "query_string" : {
                  "query" : "test"
               }
            },
            {
               "term" : {
                  "adult" : true
               }
            }
         ]
      }
   },
   "from" : 0,
   "size" : 20
}
'

Really, though, query clauses should be used for:

• full text search
• clauses which affect the relevance score

However, your adult == true clause is not being used to change the relevance, and it doesn't involve full text search. It's more of a yes/no response, in other words it is better applied as a filter clause.

This means that you need to wrap your full text query (_all contains test) in a query clause which accepts both a query and a filter: the filtered query:

curl -XGET 'http://127.0.0.1:9200/_all/_search?pretty=1'  -d '
{
   "query" : {
      "filtered" : {
         "filter" : {
            "term" : {
               "adult" : true
            }
         },
         "query" : {
            "query_string" : {
               "query" : "test"
            }
         }
      }
   },
   "from" : 0,
   "size" : 20
}
'

Filters are usually faster because:

• they don't have to score documents, just include or exclude them
• they can be cached and reused