Distributed Databases   «Prev  Next»

Steps for Offline Instantiation of Snapshot[Oracle]

  1. Call the BEGIN_INSTANTIATION procedure.
  2. Export the table data on the master site.
  3. Call the RESUME_SUBSET_OF_MASTERS procedure.
  4. FTP the export file to the remote site.
  5. Call the BEGIN_LOAD procedure.
  6. Import the table data on the remote site.
  7. Call the END_LOAD procedure.
  8. Call the END_INSTANTIATION procedure.

RESUME_SUBSET_OF_MASTERS Procedure

When you add a new master site to a master group by performing an offline instantiation of a master site, it may take some time to complete the offline instantiation process. This procedure resumes replication activity at all existing sites, except the new site, during offline instantiation of a master group.
You typically execute this procedure after executing the DBMS_OFFLINE_OG.BEGIN_INSTANTIATION procedure. You must call this procedure from the master definition site.

Note: This procedure is used to perform an offline instantiation of a master table in a multimaster replication environment. This procedure should not be confused with the procedures in the DBMS_REPCAT_INSTANTIATE package (used for instantiating a deployment template).

Adding New Master Sites with Offline Instantiation Using Export/Import

Expanding established replication environments can cause network traffic when you add a new master site to your replication environment using the ADD_MASTER_DATABASE procedure. This is caused by propagating the entire contents of the table or materialized view through the network to the new replicated site. To minimize such network traffic, you can expand your replication environment by using the offline instantiation procedure. Offline instantiation takes advantage of Oracle's Export and Import utilities, which allow you to create an export file and transfer the data to the new site through another storage medium, such as CD-ROM, tape, and DVD.
The following script is an example of how to perform an offline instantiation of a master site. This script can potentially eliminate large amounts of network traffic caused by the other method of adding a new master site to an existing quiesced master group. The script assumes that the hr schema does not exist at the new master site and instantiates this schema at the new master site. The hr schema is created automatically when Oracle is installed.