How to perform join between two indexes in ES?

I have two indexes as
Student1.csv and lecture.csv

sample student1.csv

student_id	name	Roll no
1	Amey	1
2	Neha	2
3	Shubham	3
4	Satish	4
5	Ritika	5

sample lecture.csv

lec_no	lec	student_id
1	eng	1
1	eng	1
1	eng	3
1	eng	4
1	eng	5
2	maths	1
2	maths	2
2	maths	3
2	maths	4
2	maths	5
3	sci	1
3	sci	2
3	sci	3
3	sci	4
3	sci	5
4	history	1
4	history	2
4	history	1
4	history	1
4	histoy	3
5	PT	3
5	PT	3
5	PT	3
5	PT	4
5	PT	5

both indexes have a common field student_id
I want to visualize a bar graph on which I want names of top 3 student on X-axis from (student1.csv index) and the count of student_id on Y-axis from( lecture.csv)

I want output in the following way

Elasticsearch does not support joins like that so your best bet is probably to denormalise and store student information on the lecture documents.

1 Like

So this "JOIN" feature available in elastic (subscription) Plati­num, Enter­prise mode?

No, Elasticsearch does not support joins at all.

Thanks