I need to find all issues which are appear in more than one scrum boards by using a JQL query. or is there any other way to filter those issues?.
I have posted this question on hereand there is answer for this.. the answer is
"JQL is for finding issues based on issue data. Whether an issue appears on a board is not issue data, it is board configuration. In other words, you can't do it directly. You'll need to analyze each board query to see where they might overlap."