Required settings

  • Host name
  • Port (default is 1433)
  • Service account
  • Database name
    • Make sure to enable CDC on the database and tables you want to replicate

Creating a service account

USE DATABASE_NAME;
CREATE LOGIN artie WITH PASSWORD = 'PASSWORD';
CREATE USER artie FOR LOGIN artie;
GRANT SELECT on DATABASE::DATABASE_NAME to artie;

Enabling CDC

To enable CDC for SQL server, you’ll need to enable it at the database and table level.

  1. Enable CDC for your database
USE DATABASE_NAME;
EXEC sys.sp_cdc_enable_db;

-- Now specify the retention period of your CDC logs, retention is specified as mins.
-- We recommend you setting this between 24h to 7 days
EXEC sys.sp_cdc_change_job @job_type = N'cleanup', @retention = 10080; -- 7 days
  1. Enable CDC for your tables
exec sys.sp_cdc_enable_table 
@source_schema = 'SCHEMA_NAME',
@source_name = 'TABLE_NAME',
-- You can specify the service_account as the @role_name to restrict access
@role_name = null;

Troubleshooting

Unique index override

By default, sys.sp_cdc_enable_table will use the primary keys of the table as the unique identifiers. If you are running into issues with this, you can optionally set @index_name to an unique index of your choice.

For example, if you had a table that looked like this

CREATE TABLE orders (
    id INTEGER IDENTITY(1001,1) NOT NULL PRIMARY KEY,
    order_date DATE NOT NULL,
    purchaser INTEGER NOT NULL,
    quantity INTEGER NOT NULL,
    product_id INTEGER NOT NULL,
    FOREIGN KEY (purchaser) REFERENCES customers(id),
    FOREIGN KEY (product_id) REFERENCES products(id)
);

If you don’t want to use id, you can do something like this:

ALTER TABLE orders ADD COLUMN prefix VARCHAR(255) DEFAULT 'orders' NOT NULL;
-- Create unique index
CREATE UNIQUE INDEX cdc_index ON dbo.orders (id, prefix);
-- When enabling CDC, use cdc_index instead of the primary key
EXEC sys.sp_cdc_enable_table @source_schema = 'dbo',@source_name = 'orders',
@role_name = NULL, @index_name = 'cdc_index';