Oracle 7.3.4/8i Question

I am looking to implement a system that will take a flat file of table rows and apply them to a database. The file will know the table name and the 1-3 primary keys and will be in primary key order.

The old system worked on the premise

1. It sucked out the database into a structure in memory
2. Compared keys of the flat file to that of the memory image and did one of two things.
3. if not found deleted the record in the database.
4. compared columns and updated appropriately
5. It would then reread the flat file and insert all records not present in the image file.

This process needs to be very very efficient so my question are:

1. Under 7.3.4 and 8i does it actually perform an update if values are the same for all column. This would remove the requirement to compare indivual columns
2. Can I read from a 7.3.4 database in primary key order using cursors. Some tables have over a million records and sorting is hell. (I ask this because I seem to remember that I was forced to add a where clause to force an index to be used once).

Any design examples welcome.

Regards,

Iain Received on Wed Nov 14 2001 - 01:17:06 CST