Cqrlog has option to remove duplicates from log. "Qso list/File/Remove dupes from the log"
But sometimes you may have only need to seek duplicates without removing them right away.
For this you can use command "mysql" using command terminal. It might be better than "QSO list/Filter/SQL console", but both ways will work.
If you have selected "Save log data to local machine" you have to start Cqrlog first and look what log number you want to use.
When Cqrlog is running open command terminal and give:
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