What is Replication?
MS SQL Server database replication is a technology for copying, distributing, and synchronizing data and objects from one database to another continuously or at predetermined intervals.
Types of Replication in SQL Server
There are four types of replication in MS SQL Server,
- Transactional replication
- Peer-to-peer replication
- Merge replication
- Snapshot replication
Transactional replication
Transactional replication is a technique used in Microsoft SQL Server to distribute and synchronize data from one database to another. This type of replication is commonly used in scenarios where there is a need to keep multiple databases in sync, such as in a distributed or remote environment. This article will discuss how to configure MS SQL Server Transactional Replication.
Peer-to-Peer replication
Peer-Peer publication enables multi-master replication. The publisher streams transactions to all the peers in the topology. All peer nodes can read and write changes, which are propagated to all the nodes in the topology.
Merge replication
The Publisher and Subscribers can update the published data independently after the Subscribers receive an initial snapshot of the published data. Changes are merged periodically. Microsoft SQL Server Compact Edition can only subscribe to merge publications.
Snapshot replication
The Publisher sends a snapshot of the published data to Subscribers at scheduled intervals.
Here we will learn how to configure Transactional replication.
Step 1. Prepare the Environment
Before configuring transactional replication, you must ensure a stable and reliable SQL Server environment. This includes ensuring that you have the necessary permissions to create and manage replication and that the SQL Server instances are properly configured to support replication. You also need to ensure that the databases to be replicated are compatible with transactional replication.
Step 2. Create a Publication
The first step in configuring transactional replication is to create a publication. A publication is a set of one or more articles that define the data to be replicated. To create a publication, follow these steps,
- Open SQL Server Management Studio (SSMS) and connect to the SQL Server instance.
- Expand the Replication folder, right-click the Local Publications folder, and select New Publication.
- The New Publication Wizard will start. Click Next to proceed.
- Select the database that you want to replicate and click Next.
- Select Transactional publication and click Next.
- Select the articles that you want to replicate and click Next.
- Configure the snapshot options, such as when to generate a new snapshot and where to store it. Click Next.
- Configure the subscription options, such as the type of subscription and the security settings. Click Next.
- Review the summary and click Finish
Step 3. Create a Subscription
Once you have created a publication, you need to create a subscription. A subscription is a copy of the publication on another SQL Server instance. To create a subscription, follow these steps,
- Open SQL Server Management Studio (SSMS) and connect to the SQL Server instance where you want to create the subscription.
- Expand the Replication folder, right-click the Local Subscriptions folder, and select New Subscription.
- The New Subscription Wizard will start. Click Next to proceed.
- Select the publication that you want to subscribe to and click Next.
- Configure the subscription options, such as the type of subscription and the security settings. Click Next.
- Configure the synchronization options, such as when and how to handle conflicts. Click Next.
- Review the summary and click Finish.
Step 4. Configure Replication Agents
After creating a publication and subscription, you need to configure replication agents. Replication agents are processes that manage the replication process between the publisher and subscriber. There are two types of replication agents: the Snapshot Agent and the Log Reader Agent. To configure the agents, follow these steps,
- Open SQL Server Management Studio (SSMS) and connect to the SQL Server instance.
- Expand the Replication folder and right-click the Publication folder. Select Properties.
- Select the Snapshot Agent tab and configure the options, such as the schedule and the delivery method. Click OK.
- Select the Subscription folder and right-click the subscription. Select Properties.
- Select the Subscription Options tab and configure the options, such as the schedule and the delivery method. Click OK.
Step 5. Start the Replication Process
Once you have completed the above steps, you must start the replication process. To start the replication process, follow these steps,
- Open SQL Server Management Studio (SSMS) and connect to the SQL Server instance.
- Expand the Replication folder and select the Publication folder.
- Right-click the publication and select Start Synchronizing.
- The Start Synchronizing Wizard will start. Click Next to proceed.
- Review the synchronization settings and click Next.
1. Select the subscription database and click Next.
2. Select the subscription database and click Next.
The replication process will start, and you can monitor its progress in the Replication Monitor window in SQL Server Management Studio.
Conclusion
Configuring MS SQL Server Transactional Replication can be a complex task, but it is essential for maintaining data consistency in distributed or remote environments. By following the steps outlined in this article, you can configure transactional replication in a way that meets your specific requirements.
Before deploying it in a production environment, remember to test the replication process thoroughly. With proper planning and testing, transactional replication can be a powerful tool for ensuring data consistency across multiple databases.
In the above article, we will learn how to configure Transactional replication in SQL Server. Hope this will help the readers. Happy Coding!!!