Oracle Database 21c Integration with OGG - Oracle Database 21c Database OGG Enhancements and Features!

August 22, 2021  

 

Integration of Oracle GoldenGate with Oracle Database 21c and Oracle GoldenGate Enhancements!

Oracle GoldenGate started getting intergreted with Oracle Database from the version OGG 12.1.x. Yes, Intergrated Extract and later Integrated Replicat. This is where they embedded the streams technology with OGG.

Integrated Extract and Intergrated Replicat are tightly coupled with Oracle Database. It means, these processes are integrated with Oracle Database. Hence it has fully loaded features where classic Extract or Replicat does not have as it is decuopled with Oracle Database. This was the starting phase for oracle to integrat Oracle GoldenGate with Oracle Database.

There were also other intergration to the Oracle Database like below:

1. Oracle GoldenGate Integration with DataPump (Expdp/Impdp)

2. Automatic Conflict Detecton and Resolution (AUTO CDR)

Recently, Oracle Database 21c got released on Cloud as well as On-Premisis. I found some interesting features related to Oracle GoldenGate as below.

1. Automatic CDR Enhancements

2. Improved Support for Table Replication for Oracle GoldenGate

3. LogMiner Views Added to Assist Replication

4. Oracle GoldenGate for Oracle and XStream Support for JSON Data Type.

1. Automatic CDR Enhancements:

Automatic CDR was introduced in the version of OGG 12.3 and from Oracle Database 12.2. It was a great enhancment provided by Oracle as normal. 

CDR needs so many parameter configurations which was a bit tedious. Oracle simplified the configuration of CDR by introducing Automatic CDR feature.

1. Add parameter MAPINVISIBLECOLUMNS in each replicate parameter file.

2. Connect to database and execute the below command

exec dbms_goldengate_adm.add_auto_cdr('SCHEMA','TABLE');

But by default AUTO CDR resolves the conflict using the highest or latest timestmap. This will not suit for all the applications.

From Oracle Database 21c there is an enhancement of AUTO CDR resolving the conflicts using earliest timestamp and site priority.

So with this, AUTO CDR supports as below.

1. Latest Timestamp based resolution

2. Earliest Timestamp based resolution

3. Site Priority based resolution

2. Improved Support for Table Replication for Oracle GoldenGate:

Adding supplemental log is one of the pre-requisites for Oracle GoldenGate. We need to mention the tables which needs to be replicated or captured by the Extract Process. The parameters are TABLE/TABLEEXECUTE.

Now, this has been integrated with Oracle Database 21c with a new feature OGG EXTRACT, the LOGICAL_REPLICATION clause for automatic extract of tables.

3. LogMiner Views Added to Assist Replication:

The DBMS_ROLLING package provides us with procedures to perform rolling upgrade related tasks.

From Oracle Database 21c, the package has a new parameter in the DBMS_ROLLING.set_parameter() which is BLOCK_UNSUPPORTED. This parameter blocks the replication of operations UNSUPPORTED by Transient Logical Standby.

4. Oracle GoldenGate for Oracle and XStream Support for JSON Data Type:

From Oracle 21c, the OGG supports JSON Data Type. 

References:

1. Automatic CDR Enhancements

https://docs.oracle.com/en/database/oracle/oracle-database/21/nfcon/automatic-cdr-enhancements-264574977.html

2. Improved Support for Table Replication for Oracle GoldenGate

https://docs.oracle.com/en/database/oracle/oracle-database/21/nfcon/improved-support-for-table-replication-for-oracle-goldengate-256550019.html

3. LogMiner Views Added to Assist Replication

https://docs.oracle.com/en/database/oracle/oracle-database/21/nfcon/logminer-views-added-to-assist-replication-382959480.html

4. Oracle GoldenGate for Oracle and XStream Support for JSON Data Type

https://docs.oracle.com/en/database/oracle/oracle-database/21/nfcon/oracle-goldengate-for-oracle-and-xstream-support-for-json-data-type-256120867.html

Hope this helps!

Cheers!

Ramesh.