Query multiple indexes

Elastic Stack Elasticsearch
1

As a beginner in ELK . I want ask how can I query on multiple indexes. I have below 2 indexes.

1)Product index
-id
-DisplayName

  1. ProductAssociation index
    -id
    -SourceAssociationId
    -DestinationAssociationId

Product index sample data
{
{
id:"101",
DisplayName:"CLAMP-2"
},
{
id:"201",
DisplayName:"Avenger"
},
{
id:"202",
DisplayName:"Pulsar"
}
}

ProductAssociation index sample data
{
{
id:"001",
SourceAssociationId:"201",
DestinationAssociationId:"101"
},
{
id:"001",
SourceAssociationId:"202",
DestinationAssociationId:"101"
}
}

part CLAMP-2 has association with 201,202. I want to fetch below data by part name "CLAMP-2" which is product.DisplayName
{
{
id:"201",
DisplayName:"Avenger"
},
{
id:"202",
DisplayName:"Pulsar"
}
}

2

That sounds a lot like a join between 2 indices, which Elasticsearch does not support. You either need to split this into 2 queries or restructure and denormalise your data in Elasticsearch.