How multi_match search in elastic on main object and nested array of objects? - elasticsearch

Question

I'm using elastic-search v7 and I have mapped object like below.
Items its nested array of objects.
My problem is, when I try search by multi_match items fields, its not working like I expect, result is empty. But when I try to search with query and boolean, its finds my document.
I don't correct understand what a different there, how I understand is query_search its exact matches using for filter and aggregation of data, and multi_match for full text search and autocomplete , right?
And how to find documents searching in root fields and nested fields?
{
"orders" : {
"aliases" : { },
"mappings" : {
"properties" : {
"amazonOrderId" : {
"type" : "keyword"
},
"carrierCode" : {
"type" : "text"
},
"carrierName" : {
"type" : "text"
},
"id" : {
"type" : "keyword"
},
"items" : {
"type" : "nested",
"properties" : {
"amazonItemId" : {
"type" : "keyword"
},
"amazonPrice" : {
"type" : "integer"
},
"amazonQuantity" : {
"type" : "integer"
},
"amazonSku" : {
"type" : "keyword"
},
"graingerItem" : {
"type" : "nested"
},
"graingerOrderId" : {
"type" : "keyword"
},
"graingerPrice" : {
"type" : "integer"
},
"graingerShipDate" : {
"type" : "date"
},
"graingerShipMethod" : {
"type" : "short"
},
"graingerTrackingNumber" : {
"type" : "keyword"
},
"graingerWebNumber" : {
"type" : "keyword"
},
"id" : {
"type" : "keyword"
}
}
}
}
}
}
}
multi_match request
GET orders/_search
{
"query":{
"multi_match" : {
"query": "4.48 - 1 pack - 4.48",
"fields": [
"items.amazonSku",
"carrierCode",
"recipientName"
]
}
}
}
Debugging by _explain api returns me that description
"explanation" : {
"value" : 0.0,
"description" : "Failure to meet condition(s) of required/prohibited clause(s)",
"details" : [
{
"value" : 0.0,
"description" : "no match on required clause (items.amazonSku:4.48 - 1 pack - 4.48)",
"details" : [
{
"value" : 0.0,
"description" : "no matching term",
"details" : [ ]
}
]
},
{
"value" : 0.0,
"description" : "match on required clause, product of:",
"details" : [
{
"value" : 0.0,
"description" : "# clause",
"details" : [ ]
},
{
"value" : 1.0,
"description" : "DocValuesFieldExistsQuery [field=_primary_term]",
"details" : [ ]
}
]
}
]
}
Query search
GET orders/_search
{
"query": {
"nested": {
"path": "items",
"query": {
"bool": {
"must": [
{ "match": { "items.amazonSku": "4.48 - 1 pack - 4.48"}}
]
}
}
}
}
}

Answer 1

Since you are querying on nested field items, you need to include the nested param in your query so that it searches for the nested field object
Modify your search as
{
"query": {
"nested": {
"path": "items",
"query": {
"multi_match": {
"query": "4.48 - 1 pack - 4.48",
"fields": [
"items.amazonSku"
]
}
}
}
}
}