Large data migration problems during oralce9i upgrade to oralce10g

The database used in the recently started project has been upgraded. The old system is 9i, and the new system uses 10 Gb.

Data needs to be imported from the old system at the beginning of the new system, and relevant information has been searching for these days.

Problems:

1. The old system runs 24x7. The service cannot be stopped at regular time before the new system runs.

2. The data volume is large, with at least xxxgb of data, or even TB.

 

Oracle officially recommends four upgrade methods:

The following sections describe the upgrade methods you can use to upgrade your database to the new Oracle Database 10GRelease:

· Database Upgrade Assistant

· Manual upgrade

· Export/Import

· Data Copying

The first is to use the dbua tool. The advantage is that the upgrade speed is fast. The disadvantage is that once the upgrade fails, the original database may become unavailable and the risk is high.

The second method is not carefully studied, similar to the first method.

The third method is to use exp and IMP to import data, which has many advantages. However, when the data volume is large, the waiting time cannot be accepted, causing a high time risk.

The fourth method is to directly copy data using DB link, requiring direct network connection.

The above four methods have their own advantages and disadvantages. Finally, we can see the Amadeus solution in the official Oracle case:

Using TTS for fast database upgrades with minimal downtime (PDF)

You can use transportable tablespace to copy data. TTS only takes a long time to copy the so-called metadata.

Copy is similar to file transmission speed.

Another document can also be referenced. The document says that downtime is only about 10 minutes, which is really great!