When any processing fails, the item moves to broken queue.
Does all the items in Broken Queue and in the normal queue from where agent picks up the entry belong to Same or different TABLE, i.e, entry in broken queue and normal queue stays in same or different table?
Broken Queue can be monitored from Process & Rules > Tools > Work Admin > Broken Queue Items. You can see the class mapped to this Report. Once you open the class record and check the DB connection, you can very the table name.