Hi Johan, 

Johan Hallgren [mailto:[EMAIL PROTECTED] wrote:
> 
> 
> * Is it correct that if I do the export and import as PAGES 
> (as opposed to RECORDS), I need to make a backup of my target database 
> after loading the data, before I can make any changes to the loaded tables?
> 
That's correct. The tables loaded are flagged read only then. The reason for
this behavior is the fact that when loading PAGES the database does not log
the changes in data.

> * Is it correct that changing the COLUMNCOMPRESSION to NO 
> will mean that the storage requirements of the database will be somewhat 
> larger than if it was set to yes, but it is a setting that is completely 
> transparent to
> the user of the database (e.g. I assume that a varchar(10) field still
> would behave exactly the same in SQL statements regardless of the
> setting of the COLUMNCOMPRESSION parameter)?
> 
That's correct, too.
BTW, you can switch the parameter COLUMNCOMPRESSION back to YES after loading
your data. The tables created when COLUMNCOMPRESSION was set to NO remain at no
compression, but newly created table will benefit from compression.
In case the data volume is rather small you could also use the Loader data file 
format
RECORDS to transport your data. In this case the COLUMNSCOMPRESSION can stay
YES in your target database with no problem.

> * I did have the one issue when loading that because the 
> schema contains
> a couple of circular foreign key relationships (where two tables have
> FKs that reference each other) I got a referential integrity violation
> error when first importing the catalog and then the data. 
> Instead I had
> to manually create the schema (minus the foreign keys), load the data,
> and then manually create the foreign keys.  I assume this is 
> the way it has to work, and had I not had these circular FKs, I could 
> have imported the catalog using the loader?
> 
> 
That's correct, too, for older Loader versions. The newer version of the Loader
is able to deal with this by storing the catalog into 2 files during export -
the first file contains the statements without foreign key and index definitions
and is executed before loading the data. The second portion of the catalog 
stored
in the second catalog file will be executed after the data is successfully 
loaded.

Best regards,
 Steffen
-- 
Steffen Schildberg
MaxDB Team
SAP Labs Berlin 

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