The below article tries to explain the experience between Oracle and Informatica change data capture(CDC).
Gartner’s Magic Quadrant for Data Integration Tool ( including CDC)
## The dot is the 2013 position and the black line is the movement from the 2012 position.
When evaluating a Data Integration Suite Gartner looks at connectivity, modes of interaction (CDC, bulk event), data transformation capabilities, metadata and modelling, design and development, data governance, deployment options, operations and administration, architecture, service enablement.
So, what does it take to use Oracle GoldenGate?
First off, it takes money, as in more of it, because of how Oracle has chosen to license it. Its cost is tied to the database server licensing metric, so for one processor (perpetual), you’re looking at $17,500 (Year 2011) for licensing and $3,850 for the first year’s support. Streams, in comparison, is included in whichever edition you use.
Finally, you have to get used to a new language replete with hundreds of new keywords using a not too complex syntax. The running of GoldenGate can be 100% command line interface. There is an optional add on product (Director) which offers a GUI-based centralized management feature.
There are several generalized use cases for this kind of database replication technology:
- Unidirectional replication (source to target)
- Broadcast (one source, multiple targets)
- Consolidation (multiple sources, one target)
- Bidirectional synchronization (active-active failover)
- Peer-to-Peer (load balancing with high availability)
- Cascading (multi-tier scalability)
DML and DDL handling
Unlike Informatica PWX CDC, however, Oracle GoldenGate is capable of replicating certain DDL changes as well, making the system more resilient to unexpected source table changes (adding a column, changing a column length, etc). This adds a level of complexity to the installation, however, and in some environments it may be better to control these DDL changes through proper production change control processes.
Supported source and target for Oracle GoldenGate
Advantages of GoldenGate over Infa PWX CDC for Oracle include:
- Simple installation and configuration
- DDL replication capabilities (if your source databases can live without the recyclebin)
- JMS messaging capability, to trigger downstream ETL or other processes
Advantages for Infa PWX CDC include:
- Mainframe databases can be used as sources
- Automatic triggering of Informatica PowerCenter, for near-zero latency configurations
Depending on your technical environment, enterprise licensing agreements and vendor relationships, both are good options for large enterprises.
However, we have to give Oracle GoldenGate a slight edge, due to the DDL synchronization capabilities explored above and its relative simplicity of configuration. As Oracle further develops capabilities, such as Veridata and the new GoldenGate Monitor released in 2012, GoldenGate will be well-positioned for enterprise deployment.
It also appears that GoldenGate is a strategic technology for Oracle, with roadmaps showing aggressive development inline with Oracle’s database strategy. It seems likely that GoldenGate will eventually replace Oracle’s built-in replication technologies.
By comparison, Informatica has not significantly changed PowerExchange CDC for Oracle in recent years. Perhaps, with this new competition from GoldenGate, some improvements and a more active development program will be announced at the upcoming Informatica World 2013 in June.
credit : Matt http://blog.mdbbi.com/
Now, for technical folks , just to get a feel of how the entire configuration works please find below an extract from Oracle Documentation
Asynchronous AutoLog Change Data Capture Configuration
Figure 1 shows a typical Change Data Capture asynchronous AutoLog configuration in which, when the log switches on the source database, archiver processes archive the redo log file on the source database to the destination specified by the LOG_ARCHIVE_DEST_1 parameter and copy the redo log file to the staging database as specified by the LOG_ARCHIVE_DEST_2 parameter. (Although the image presents these parameters as LOG_ARCHIVE_DEST_1 and LOG_ARCHIVE_DEST_2, the integer value in these parameter strings can be any value between 1 and 10.)
Note that the archiver processes use Oracle Net to send redo data over the network to the remote file server (RFS) process. Transmitting redo log files to a remote destination requires uninterrupted connectivity through Oracle Net.
On the staging database, the RFS process writes the redo data to the copied log files in the location specified by the value of the TEMPLATE attribute in the LOG_ARCHIVE_DEST_2 parameter (specified in the source database initialization parameter file). Then, Change Data Capture uses Oracle Streams downstream capture to populate the change tables in the change sets within the AutoLog change source.
Fundamentals of Oracle GoldenGate, Steve Callan(Jan 12, 2011) , http://www.databasejournal.com/features/oracle/article.php/3919876/Fundamentals-of-Oracle-GoldenGate.htm
Matt, First impressions: Oracle GoldenGate vs. Informatica PWX CDC for Oraclehttp://blog.mdbbi.com/post/43533069697/first-impressions-oracle-goldengate-vs-informatica