Tech

 The Change Data Capture technology was first launched as a built-in feature of the Oracle database in the 9i version. It was very effective in tracking and recording all changes made in user tables in a database. These changes were stored in change tables for use in ETL applications. The data could then be processed and loaded into other data warehouses and databases. The first release of the Oracle Change Data Capture functioned through triggers placed in the source. However, this method did not find favor with the DBAs as it was too invasive.   Subsequently, a new and improved version of the Oracle Change Data Capture, named Oracle Streams,was introduced with the 10g version of the Oracle database. It leveraged the redo logs of the source database and the built-in replication tool of Oracle. Streams was a very optimized process to identify and move change data to a target database without adversely affecting the performance of the source database. Unfortunately, despite it...

 Change Data Capture is a set of software design patterns to track and determine data that has changed to enable taking necessary action on it. The CDC approach is data integration based on the principle of identification, capture, and delivery of the changes made to a source enterprise database. Change Data Capture most often occurs in data warehouse environments. This is because capturing and preserving the state of the data is the basic function of a data warehouse though CDC can be used in any data repository or database system. Change Data Capture records insert, update, and delete activity that applies to a SQL Server table and puts the details of the changes available in a relational user-friendly format. Any column information and the metadata required for recording the changes to a target database are captured for the modified rows. These are stored in change tables that mirror the column structure of the tracked source tables. The most simplified change data capture form...