Elastic Search: Combining multiple search results

Question

i have a tricky case which I dont know how to solve.

I have 2 queries: q1 and q2 The 2 queries result in r1 and r2

each of the results is sorted in a special order.

As an overall search result i want to return a concatenation of r1+r2 before returning it to the application.

The reason is that i would break the pagination if I do it later.

Any idea? Its probalby an easy question but I am stuck on this...

PS:

we also experimented with sorting first by a priary sort criteria and then by the score.. but the score always breaks the first sort criteria somehow we cant get the score working only within its bucket.

Answer 1

you can boost your fruits with a factor, so that their score will be always higher than the vegetable score, yet preserving the order. You can do that with a simple weight function score query

PUT /test

POST /test/fruits/1
{
    "field": "hello world"
}

POST /test/fruits/2
{
    "field":"hello"
}

POST /test/veges/1
{
    "field": "hello world"
}

POST /test/veges/2
{
    "field":"hello"
}

POST /test/_search
{

    "query": {

        "function_score": {
            "query": {
                "match": {
                   "field": "hello"
                }   
            },
            "functions": [
                {
                    "filter": {
                        "type": {
                           "value": "fruits"
                        }
                    },
                    "weight": 2
                }
            ]
        }
    }
}

However please note that if you do that on a big database then it will be very resource consuming to page down to the first vegetable. I would consider rebuilding your UX so that fruits and vegetables are actually separate requests. You can do that with a _bulk endpoint and send two separate queries per each document type in one server API call, and return both results back.

Answer 2

建议使用弹性搜索的组合查询功能 。