Unable to get users for some issues

[Ratnesh Saxena]

In JiraIssues table there is a column name 'reporter' which contains is mapped to the cwd_user table and contains the username of the person.

I have found there are some issues whose reporter doesn't exist in the cwd_user table but on UI email id is showing correctly.

Please help me to understand the mapping of Jira Issues to the with User table.

[Nic Brough -Adaptavist-]

Some users in cwd_user will have login ids, others uids, and you're going to need to do multiple conditional joins to work out who is who.

Please, stop reading the database, it's complex and not designed for reporting, as you've discovered.  Please use the UI and REST API as intended - these will both give you consistent and correct answers as you expect them.