Skip to main content

All That You Need to Know About SQL Server CDC

 In the modern business environment, data is to be protected data from breaches. Keeping this in mind, major database solution providers like Oracle and Microsoft had launched various initiatives like triggers, complex queries, timestamps, and data audits. The first player was Microsoft when in 2005 it launched SQL Server Change Data Capture (CDC) with “after date”, “after delete”, and “after insert” features. A modified version, introduced in 2008 and still being usedcan monitor and capture any changes made to the SQL Server database.


The functioning of the SQL Server change data capture feature is not a complex one. All changes like insert, update, and deletemade to a SQL Server tableare captured by Change Data Capture which then enters the details of the modifications in a user-friendly relational format.

Information about metadata and column structure necessary to apply changes to the target database are captured for the changed rows and stored in change tables. These tables replicate the column structure of the tracked source tables. Table-valued functions that enable users to have uninterrupted access to the full changed data are provided by SQL Server change data capture.

The source of CDC is the transaction log of the SQL Server. All changes like inserts, updates, and deletes that are applied to the tracked source tables are added to the log through entries describing the changes. Hence, the main input in the SQL Server change data capture process is the SQL Server log with modifications in the source database like Insert, Update, and Delete being tracked by the SQL Server Change Data Capture. 

Comments

Popular posts from this blog

Capturing Data with the SAP Extractor

The SAP Extractor is a program in SAP ERP that can be both customized or taken from a standard Data Source. It prepares and captures data through an extract structure that can be transferred to the Business Warehouse of SAP. Both the options of the SAP Extractor help to describe a delta load process or various types of full load. The SAP BW can remotely access the various data transfer activities of the SAP Extractor . For more on SAP Extractor, click here. SAP Extractor executes SAP data extraction in three ways. The first is Content Extraction used to extract BW content, FI, HR, CO, SAP CRM, and LO cockpit. The second is Customer-Generated Extraction where the SAP Extractor is used for LIS, FI-SL, CO-PA. The third is Generic Extraction which is based on DB View, Infoset, Function Modules. The SAP Extractor used for a specific extraction activity depends on the particular needs of an organization. Data capturing and extraction with the SAP Extractor is initiated with the h...

The Evolution of Technology of Oracle Change Data Capture

Oracle change data capture ( CDC) was first launched with the 9i version as an in-built tool of the Oracle database. It was a tool that recorded and monitored all changes made in the user tables in a database. These changes were then stored in change tables and used in ETL applications for later processing and transferring to other data warehouses and databases. The release version of Oracle change data capture   had triggers placed in the source database. However, database administrators found this technology very invasive and did not favor it. Ultimately, Oracle changed the Oracle change data capture   technology and released it with the 10g version after naming it Oracle Streams.  The working of this release was different. Oracle change data capture   used the redo logs of the source database along with a replication tool of Oracle Streams. This technology turned out to be very successful and a highly optimized method to identify and move change data to a target ...

The Working of Microsoft SQL Server CDC

  Modern-day businesses have to preserve historical data and take measures to prevent data breaches. In this regard, Microsoft took the lead in 2005 when it launched the SQL Server CDC. The 2005 version of SQL Server CDC   had certain flaws which were ironed out in an updated release in 2008. Some of the functionalities included tracking and capturing all changes that take place in the SQL Server database tables without taking the help of additional programs and applications. Till 2016, SQL Server CDC   was offered by Microsoft in its high-end Enterprise editions but later was available in the Standard version too. SQL Server CDC   captures and records all activities like Insert, Update, and Delete applied to a SQL Server. Column information and metadata required for posting changes to the target database are recorded in modified rows that are then stored in change tables representing the architecture of the columns in the tracked source tables. SQL Server CDC ...