Use the action and error to determine the cause of the failure and resubmit the request. The error returned was 15517: 'Cannot execute as the database principal because the principal "dbo" does not exist, this type of principal cannot be impersonated, or you do not have permission.'. The failure occurred when executing the command 'SetCDCTracked(Value = 1)'. Msg 22830, Level 16, State 1, Procedure sp_cdc_enable_db_internal, Line 186Ĭould not update the metadata that indicates database AdventureWorks2008R2 is enabled for Change Data Capture. Run a select before and after so that we can see the changes. The code below updates three columns, only two of which are in the list of columns to be detected by CDC. However Microsoft recommend that these tables are not accessed directly and that the functions they provide are used instead, which I'll demonstrate below.įirst I'll make some changes to the table so we can see how they are picked up by CDC. Open up 'System Tables' under 'Tables' then you'll see a number of new tables as shown below : These are named cdc._capture and cdc._cleanup (replace with the There will be two new jobs as shown below. If you look at the SQL Server agent jobs in Object Explorer Now that CDC is set up I'll show you what changes it has made to the database. sp_cdc_get_captured_columns = 'SQLMattersDemo' Get information about the columns that are being captured for this capture instanceĮXEC sys. Can also see if cdc tracking is occurring on a table by checking sys.tables List metadata about cdc config on the current database :ĮXEC sys. List all databases and whether they have CDC enabled : The followingĬommands will list which databases, tables and columns have CDC enabled : To review the current CDC settings on the database. That is all that is required to set up CDC !īefore we look at where the captured data changes are stored, I'll briefly show you how The is a name that identifies this cdc instance (more on this later). Note that you do need to include the column (or columns) that make up the primary key so that theĬDC mechanism can uniquely identify a row (though instead of a primary key it's also possible to specify a separate unique index for this using If I had left the then all columns would have been tracked. In this case I've chosen to track changes on the Production.Product table, on the Name, Color and ProductId columns. Select name,is_tracked_by_cdc from sys.EXEC sys. How to know on which tables cdc is enabled? If is_cdc_enabled is 1 then CDC is already enabled for the database name If is_cdc_enabled is 0 then CDC is not enabled for the database Select name,is_cdc_enabled from sys.databases where name = 'test' How to know on which databases cdc is enabled? CDC is depenedened on sql server agent and when cdc is enable two jobs will be created. The column _$operation IN CHANGE TABLE(Tablename_CT) records the operation that is associated with the change: Run DML changes on source tables and you can observe changes being recorded in the associated CT tables. How to Enable Change Data Capture on Azure SQL Databasesġ.Database level 2.Table level -Enable CDC on database level Tracking data changes for audit purposes ,To perform analytics on change data ,Execute ETL operations to move all the data changes in the OLTP system to data lake or data warehouse,Event based programing that provides instantaneous responses based on data change (E.g.: Dynamic Product pricing). However, on Azure SQL Databases, CDC provides a scheduler which automatically runs the capture and cleanup processes, which are run as SQL Server Agent jobs on SQL Server and on Azure SQL Managed Instance.ĬDC is a widely used feature by enterprise customers for a variety of purposes: Now in public preview, CDC in Azure SQL Databases offers a similar functionality to SQL Server and Azure SQL Managed Instance CDC. The change tables provide a historical view of the changes made over time to source tables. Changes are captured by using a capture process that reads changes from the transaction log and places them in corresponding change tables. In early June 2021 Microsoft announces the public preview of change data capture (CDC) in Azure SQL Databases, a feature that has been requested by multiple customersĬhange data capture (CDC) records insert, update, and delete activity that applies to tables in SQL Server, Azure SQL Managed Instance or Azure SQL Databases.
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