How to search for a term and match a boolean condition - elasticsearch

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