Are you still running on a Legacy ERP on Client-Server technology - Oracle D2K or VB?
In the age of Internet when everything is going online there are companies still running ERP on client server technology. They think it is a overhead to invest again on a system which they invested about 6-7 or more yrs back. They are losing business and money as the information is not available on time to take business critical decisions.
We happen to spend a full day while trying to figure out the Oracle 11g database connection using Xampp PHP OCI8 on 32 bit windows7 platform. After doing number of configuration like this on other platforms it was really frustrating.
If you want to enable or disable all constraints which is normally done in datawarehousing jobs you are likely to get two errors ORA-02270: no matching unique or primary key for this column-list or ORA-02297 cannot disable constraint (SYS_C0010965) - dependencies.
To avoind this you should enable or disable constraint in a order. To disable all constraints use "order by constraint_type desc" ie. disable foreign ket first and then Primary key. Likewise if you are enabling do it in reverse order. for eg. "order by constraint_type"