while upgrading to PeopleTools 8.59.15 it was unable to create a unique index on PS_PT_PORTAL_MRU
The problem with this table (Portal nav most recently used) is the structure of this table and the keys has changed and now it has TONS of duplicate keys. I have tried 2 workarounds from Oracle, DOC IDs 2802604.1 (I had to fix a sql syntax error) and 2887647.1. Both of these contained sql scripts to remove the duplicates but they just run forever and show no signs of ever completing. Oracle rep says he has no knowledge of any other customer having a problem fixing this. I don't know exactly what this table is used for but I suggested