Query Showing blank result

Couchbase Server
1

I have data in my bucket it’s also showing count.
but when I am firing query it’s showing the blank result. I already created primary index.
What are the possibilities? please help me out.

2

Check how many entries in the index. what is your query and sample document

3

How to check entry in index?
In dataset I have 15 document and 1 B records.

But its showing blank result in simple query.

Select * from data limit 1;

4

Check UI primary index stats.
OR drop and create primary index

5

When we are doing high data load then we are facing problem. That time are queries are failer.
What we can do at that time ?