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oracle-databasemigrationexadata

Oracle application - migration to Exadata server

We have an upcoming migration of our Oracle database to an Exadata server. I want to clarify some issues I have thought of:

  • Will there be any issues with the code - performance issues? Exadata has another type of optimizer, it doesn’t uses indexes, has a columnar optimizer, if I’m not misleading,
  • Currently there are some import or export files generated on the database server (accessed via Filezilla). I understand that at Exadata the database server is inaccessible, and I suspect that either:
    • we will have to move those files to another server - Oracle knows only FTP (which has ports closed at our client) -> how do we write / read from another server? (as far as I understand, they would like to put all the files on the WAS server)
    • or we will need to import the files into the table using the java application and process them from there (and the same with the exported files).
  • Files that come automatically from other applications can be written to the database server? Or we have the same problems as for the manual part.
  • We have plenty of database jobs that run KSH scripts on the database server - is there a problem with them? I understand they should also be moved to the WAS server, but I do not know how Oracle will call them from there.
  • Will there be any problems with Jenkins deployments? Anything changed? Here we save the SQL/PLSQL sources in some XML files, from which the whole application is restored (packages, configuration tables, nomenclatures ...) (with the exception of the working data) (the XML files are read through a procedure from an oracle directory).

If you can think of any other issues concerning this migration, any problems you have encountered during or after the migration to Exadata, please share!

Thank you,

Solution

  • Step by step:

    1. On exadata you are going to have the same optimizer behaviour with some improvements because the exadata may improve full table scan performance thanks to smart full scans. Indeed the exadata is able to avoid retrieving data blocks in fts because it knows in advance they do not contain neeeded data.
    2. In the exadata you can export to external servers DBFS file systems, that might be useful for external tables, imports/exports and so on.
    3. You can write your files on the DBFS you can configure.
    4. You could use your DBFS, if you want the ksh files are accessed from outside your exadata.
    5. Let your oracle directory point to a directory in the DBFS file system where you put your xml files and you are done.