During server reinstall process we had to use exp/imp Oracle utils to backup/restore data.
For some strange reason our new database now works slower than old one. I have compared internal structure of old and new databases using Toad and found some differences in indexes and constraints lists.
Some indexes/constraints which exists in old database doesn't exist in
the new one. And strangely there are some indexes/constraints in new database which i can't find in the old one.
The import string used was
imp.EXE FEEDBACK=100000 BUFFER=4000000 COMMIT=N USERID=.... FILE=D:\BACKUP\file.dat LOG=D:\BACKUP\R_SPECTRUM.log FROMUSER=SPECTRUM TOUSER=SPECTRUM IGNORE=Y