7 Configuring Oracle GoldenGate Apply
Topics:
- Prerequisites for Configuring Replicat
This topic provides the best practices for configuring Replicat. - What to Expect from these Instructions
These instructions show you how to configure a basic Replicat parameter (configuration) file. - Creating a Checkpoint Table
The checkpoint table is a required component of Replicat. - Configuring Replicat
Configure a Replicat process to configure Replicat against a pluggable database. Replicat can operate in any mode within a pluggable database. - Next Steps
Once you have created a basic parameter file for Replicat, see the following for additional configuration steps.
Prerequisites for Configuring Replicat
This topic provides the best practices for configuring Replicat.
The guidelines to follow before configuring Replicat are:
-
Create the Oracle GoldenGate instance on the target system by configuring the Manager process.
See How to Add a Replicat in Using the Oracle GoldenGate Microservices Architecture.
Note:
To switch an active Replicat configuration from one mode to the other, perform these configuration steps and then see Administering Oracle GoldenGate.
Parent topic: Configuring Oracle GoldenGate Apply
What to Expect from these Instructions
These instructions show you how to configure a basic Replicat parameter (configuration) file.
Your business requirements probably will require a more complex topology, but this procedure forms a basis for the rest of your configuration steps.
By performing these steps, you can:
-
get the basic configuration file established.
-
build upon it later by adding more parameters as you make decisions about features or requirements that apply to your environment.
-
use copies of it to make the creation of additional Replicat parameter files faster than starting from scratch.
Note:
These instructions do not configure Replicat to apply DDL to the target. To support DDL, create the basic Replicat parameter file and then see Configuring DDL Support for configuration instructions.
Parent topic: Configuring Oracle GoldenGate Apply
Creating a Checkpoint Table
The checkpoint table is a required component of Replicat.
A Replicat maintains its recovery checkpoints in the checkpoint table, which is stored in the target database. Checkpoints are written to the checkpoint table within the Replicat transaction. Because a checkpoint either succeeds or fails with the transaction, Replicat ensures that a transaction is only applied once, even if there is a failure of the process or the database. See Before Creating Replicat in the Using the Oracle GoldenGate Microservices Architecture to learn to create checkpoint tables from the Microservices web UI.
Note:
This procedure installs a default checkpoint table, which is sufficient in most
cases. More than one checkpoint table can be used, such as to use a different
one for each Replicat group. To use a non-default checkpoint table, which
overrides the default table, use the CHECKPOINTTABLE
option of
ADD REPLICAT
when you create Replicat processes in the
steps in Instantiating Oracle GoldenGate Replication. .
- Adding the Checkpoint Table to the Target Database
- Specifying the Checkpoint Table in the Oracle GoldenGate Configuration
- Disabling Default Asynchronous COMMIT to Checkpoint Table
Parent topic: Configuring Oracle GoldenGate Apply
Specifying the Checkpoint Table in the Oracle GoldenGate Configuration
To specify the checkpoint table in the Oracle GoldenGate configuration:
Parent topic: Creating a Checkpoint Table
Disabling Default Asynchronous COMMIT to Checkpoint Table
When a nonintegrated Replicat uses a checkpoint table, it uses an asynchronous COMMIT
with the NOWAIT
option to improve performance. Replicat can continue processing immediately after applying this COMMIT
, while the database logs the transaction in the background. You can disable the asynchronous COMMIT
with NOWAIT
by using the DBOPTIONS
parameter with the DISABLECOMMITNOWAIT
option in the Replicat parameter file.
Note:
When the configuration of a nonintegrated Replicat group does not include a checkpoint table, the checkpoints are maintained in a file on disk. In this case, Replicat uses COMMIT
with WAIT
to prevent inconsistencies in the event of a database failure that causes the state of the transaction, as in the checkpoint file, to be different than its state after the recovery.
Parent topic: Creating a Checkpoint Table
Configuring Replicat
Configure a Replicat process to configure Replicat against a pluggable database. Replicat can operate in any mode within a pluggable database.
These steps configure the Replicat process.
Note:
See Administering Oracle GoldenGate for important information about making configuration changes to Replicat once processing is started, if using integrated Replicat.
Parent topic: Configuring Oracle GoldenGate Apply
Next Steps
Once you have created a basic parameter file for Replicat, see the following for additional configuration steps.
Configuring Capture in Classic Mode or Configuring Capture in Integrated Mode if you have not configured capture yet.
Additional Configuration Steps For Using Nonintegrated Replicat (if using nonintegrated Replicat)
Additional Oracle GoldenGate Configuration Considerations
Configuring DDL Support (to use Oracle GoldenGate DDL support)
Parent topic: Configuring Oracle GoldenGate Apply