How to join 2 indexes at query time

Join two index

# delete old index if exists
curl -XDELETE 'http://localhost:9200/offerindex?pretty'
curl -XDELETE 'http://localhost:9200/categoryindex?pretty'

# Create Index 
curl -XPUT 'http://localhost:9200/offerindex?pretty' -d '{}'
curl -XPUT 'http://localhost:9200/categoryindex?pretty' -d '{}'


curl -XPUT 'http://localhost:9200/offerindex/offertype/1?pretty' -d '{"skuid": "1983001", "offer_id": "promo00001,promo00002,promo00003"}'
curl -XPUT 'http://localhost:9200/offerindex/offertype/2?pretty' -d '{"skuid": "1983002", "offer_id": "promo00001,promo00002"}'
curl -XPUT 'http://localhost:9200/offerindex/offertype/3?pretty&refresh=true' -d '{"skuid": "1983003", "offer_id": "promo00001,promo00003"}'

curl -XPUT 'http://localhost:9200/offerindex/offertype/1?pretty' -d '{"skuid": "1983004", "offer_id": "promo00001,promo00002,promo00003"}'
curl -XPUT 'http://localhost:9200/offerindex/offertype/2?pretty' -d '{"skuid": "1983005", "offer_id": "promo00001,promo00002"}'
curl -XPUT 'http://localhost:9200/offerindex/offertype/3?pretty&refresh=true' -d '{"skuid": "1983006", "offer_id": "promo00001,promo00003"}'


curl -XPUT 'http://localhost:9200/categoryindex/categorytype/1?pretty' -d '{"skuid": "1983001", "category": "Flat TV"}'
curl -XPUT 'http://localhost:9200/categoryindex/categorytype/2?pretty' -d '{"skuid": "1983002", "category": "Flat TV"}'
curl -XPUT 'http://localhost:9200/categoryindex/categorytype/3?pretty&refresh=true' -d '{"skuid": "1983003", "category": "Flat TV"}'

curl -XPUT 'http://localhost:9200/categoryindex/categorytype/4?pretty' -d '{"skuid": "1983004", "category": "Mobile"}'
curl -XPUT 'http://localhost:9200/categoryindex/categorytype/5?pretty' -d '{"skuid": "1983005", "category": "Mobile"}'
curl -XPUT 'http://localhost:9200/categoryindex/categorytype/6?pretty&refresh=true' -d '{"skuid": "1983006", "category": "Mobile"}'