Application of Oracle Data Replication Technology in Packaging Enterprises (in)

2 Oracle Advanced Replication Technology Replication is the process of transferring database objects from a source site to a destination site on an established data link in a distributed environment of two or more database systems. Replicated objects can be tables, views, triggers, indexes, synonyms, etc. Source sites refer to changes in their data. Oracle provides two replication technologies: source group replication and snapshot replication. Among them, source group replication is bidirectional, and snapshot replication is unidirectional. This system only modifies the database after the anti-counterfeit identification generation system generates a new identification code, and the rest of the sites do not modify the database contents. Therefore, the snapshot copy is used. The snapshot station (destination site) saves the snapshot of the source site object and is mainly used to ensure the availability of the system. Improve query speed while ensuring data consistency.
Snapshot replication includes a copy of a primary table or a subset of it, propagates and applies changes from the source site to the snapshot site using the "delay remote procedure call" mechanism, and refreshes the snapshot site at regular intervals after the source site refreshes. When the user requests refresh individually. Any changes to the source table after the last refresh are also propagated and applied to the snapshot. If a snapshot site is not ready when it is refreshed, this refresh will be saved in the local queue and will be executed after the system is ready.

3 oracle advanced replication technology application examples to achieve a more complex data replication process, follow certain steps to complete. Oracle provides a visual copy management tool, you can easily create a copy environment through the wizard, you can also use the command method to establish, the following gives the specific steps of the command method to copy the project and its precautions.
a. Prepare data replication. Check whether the installed database supports advanced replication: use system login, use the selec * from v $ option wher parameter='Advancedlephcation'; command, if the value is TRUE, then support advanced replication.
Set the database initialization parameter file mit. Ora, then restart the database for the parameters to take effect.
Db-domain=jj.com. Cn # specify the database domain name global-names = true # global database name: db-name ten "." Ten db-domain
Job-queue-interval:60 # Wake up the process once every 60 seconds once the previous machine configuration, define the database name and IP address:
Modify tnsnames. The connection string in ora ensures that ors can access webdb and run $tnsping ors webdb: (DESCRIPTION: (AD-DRESS-LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=10.1.192.168) PORT:1521)))
(CONNECT-DATA=(SERVICE-NAME=webdb)))#Listener The port number is 1521; (to be continued)