Oracle 9 Production - Integration refresh: questions

Question

Hello, I will have to proceed with Oracle 9 database refresh from production server to integration server. 5 biggest schemas must be exported and imported. They constitute 97% space used in a database. This is very big database so I would like to be sure that everything will go smoothly. That is why i want to ask you some questions. Have you got any clues for me before I start with exp/imp? From my side i will tell you that I will have to exp/imp schema by schema because there is small space both on production and integration disk for a dump. First thing I thought are dependencies between schemas that are exported and that which are not, and also between schemas that are exported/imported one by one.
This is procedure that I plan:
For every schema that is to be refreshed
1. Export schema with ROWS=N CONSTRAINTS=Y
2. EXPORT schema with ROWS=y CONSTRAINTS=N
3. Import schema from step one
4. Disable all the foreign key constraints using ALTER TABLE DISABLE CONSTRAINT.
5. Import schema with rows
ALTER TABLE ENABLE CONSTRAINT
With above procedure i think that I will avoid problems with dependencies between schemas exported/imported one by one. But my concern is if there are any dependencies between those schemas and schemas that are not exported. Is there an way to check it before refresh ?
Are there any details that i forgot to mention and i should be aware of?

Answer 1

If the issue is disc space, then go via a pipe: create the pipe on the source server with mknod, and use NFS to make the file system containing the pipe visible on the destination server. Then you can start the import reading from the pipe, and start the export writing to the pipe. That way you do the whole job (all the schemas) in one exp/imp run, without staging anything on disc, and no dependency issues.
Any good?