Nested Query Elastic Search - spring

Question

Currently I am trying to search/filter a nested Document in Elastic Search Spring Data.
The Current Document Structure is:
{
"id": 1,
"customername": "Cust#123",
"policydetails": {
"address": {
"city": "Irvine",
"state": "CA",
"address2": "23994384, Out OF World",
"post_code": "92617"
},
"policy_data": [
{
"id": 1,
"status": true,
"issue": "Variation Issue"
},
{
"id": 32,
"status": false,
"issue": "NoiseIssue"
}
]
}
}
Now we need to filter out the policy_data which has Noise Issue and If there is no Policy Data which has Noise Issue the policy_data will be null inside the parent document.
I have tried to use this Query
{
"query": {
"bool": {
"must": [
{
"match": {
"customername": "Cust#345"
}
},
{
"nested": {
"path": "policiesDetails.policy_data",
"query": {
"bool": {
"must": {
"terms": {
"policiesDetails.policy_data.issue": [
"Noise Issue"
]
}
}
}
}
}
}
]
}
}
}
This works Fine to filter nested Document. But If the Nested Document does not has the match it removes the entire document from the view.
What i want is if nested filter does not match:-
{
"id": 1,
"customername": "Cust#123",
"policydetails": {
"address": {
"city": "Irvine",
"state": "CA",
"address2": "23994384, Out OF World",
"post_code": "92617"
},
"policy_data": null
}

Answer 1

If any nested document is not found then parent document will not be returned.
You can use should clause for policy_data. If nested document is found it will be returned under inner_hits otherwise parent document will be returned
{
"query": {
"bool": {
"must": [
{
"match": {
"customername": "Cust#345"
}
}
],
"should": [
{
"nested": {
"path": "policydetails.policy_data",
"inner_hits": {}, --> to return matched policy_data
"query": {
"bool": {
"must": {
"terms": {
"policydetails.policy_data.issue": [
"Noise Issue"
]
}
}
}
}
}
}
]
}
},
"_source": ["id","customername","policydetails.address"] --> selected fields
}
Result:
{
"_index" : "index116",
"_type" : "_doc",
"_id" : "f1SxGHoB5tcHqHDtAkTC",
"_score" : 0.2876821,
"_source" : {
"policydetails" : {
"address" : {
"city" : "Irvine",
"address2" : "23994384, Out OF World",
"post_code" : "92617",
"state" : "CA"
}
},
"id" : 1,
"customername" : "Cust#123"
},
"inner_hits" : {
"policydetails.policy_data" : {
"hits" : {
"total" : {
"value" : 0,
"relation" : "eq"
},
"max_score" : null,
"hits" : [ ] --> nested query result , matched document returned
}
}
}
}