Database Migration 1

[Yarka]

Hi,
We need to do a database migration from a server to another. The two servers run oracle 9i. What steps we must do for do it?
What different ways exist? Which is the best?

Txs.

 

[SantaMufasa]

If either the Oracle db version or the operating systems differ between your target and your source db, then the most popular migration option is to export ("exp") from the source db, then import ("imp") into the target db. This also gives you the advantage of reorganising and defragmenting your data. This method is called a "logical" migration.

As you said, both servers run the same Oracle version. I presume they are the same operating system, as well. If this is the case, then you can do a "physical" migration, which means that you copy all database files from the source db to the target db. This means that you copy:

1) control files
2) database data files (that support your tablespaces)
3) on-line redo log files

You should also copy over the init<SID>.ora file to ensure that the behaviours of the two dbs are identical.

This method has a couple of limitations/downsides:

1) The paths relating to the Oracle files (listed above) should be the same (at least initially), and
2) The database name of the target db will be the same as the database name of the source db. (This is not too big a deal since you can certainly change the name of the Oracle instance, the global db name, and also the name of the Oracle-connection alias by using a different name in the tnsnames.ora.)

This second method is generally much faster, since copying files is quicker than having to process the contents of exp/imp dump files.

Let us know if you have followup questions.

Mufasa
(aka Dave of Sandy, Utah, USA)
[I provide low-cost, remote Database Administration services: www.dasages.com]