Change data capture overview - connect_cdc_sqdata - Latest

Connect CDC (SQData) Change Data Capture

Product type
Software
Portfolio
Integrate
Product family
Connect
Product
Connect > Connect CDC (SQData)
Version
Latest
Language
English
Product name
Connect CDC (SQData)
Title
Connect CDC (SQData) Change Data Capture
Copyright
2024
First publish date
2000
Last edition
2024-09-05
Last publish date
2024-09-05T15:00:09.754973

Connect CDC (SQData) provides an efficient and effective mechanism for propagation and/or replication of data utilizing two components; Data Capture Agents and what we refer to as an Engine. Connect CDC SQData supports both homogeneous and heterogeneous environments including zOS (mainframe), Linux and Windows operating systems. Source and target data may utilize different data structures, database management systems and operating systems. Supported sources including Db2/z, IMS, VSAM, Db2/LUW (UDB) and Oracle. Targets include all supported sources as well as any relational database supported by ODBC and streaming Kafka and HDFS targets. Relational databases can be running on premise or in the cloud such as AWS RDS. Engines need not run on the same platform as the target and are most commonly run on Linux.

While the configuration and operation of the Apply Engine is virtually identical on all platforms, the Connect CDC SQData Capture Agents operates under constraints that vary from one platform to another. To accommodate those constraints Capture utilizes various forms of Log Readers and Exits.

Near Real-Time data capture is accomplished on most platforms using the transaction log, maintained by the database manager for the purpose of database recovery. Historically, these logs have been the source of data for other purposes, including audit or replication once the database manager has been configured to include additional information required by the non-recovery related activities. The impact of larger logs is a minor inconvenience compared to the additional processing required by database trigger capture methods.

Note: The "Endianess" of the source data platform is a consideration for Data Capture and then only when the Capture Agent runs remotely on a platform other than the database server. The nature of the API's used to capture the data and the client side software provided for accessing those databases remotely requires both the Database and Capture Agent platforms to utilize the same encoding scheme. The methods used to transport captured data to Apply Engines, generally running on other remote platforms, lifts this restriction making it possible to use the most cost effective platforms for Apply Engines.