Database monitoring is the most essential job of any database administrator. Big organizations and companies have multiple database servers that are located either in the same data center or in the geographically different data centers. Read More
Database replication is the technology to distribute data from the primary server to secondary servers. Replication works on Master-slave concept where Master database distributes data to one or multiple slave servers. Replication can be set up between multiple SQL Server instance on the same server, OR it can be set up between multiple database servers within same or geographically separated data centers. Read More
What is the MERGE statement?
Using the MERGE statement, we can change data in a target table based on data in a source table. Using it, we can execute INSERT, UPDATE and DELETE on the target tables within a single query block. It joins both tables using columns, common in both tables like the primary key. Based on how column data matches, changes apply to data of target table. The following image illustrates how “MERGE” works:
The concept of snapshot replication is simple. It generates and distributes the snapshot of schema and data of articles, appeared at a specific time and updates the changes on subscriptions. When we create snapshot replication, SQL Server creates a Snapshot Agent Job which generates a snapshot of publication database objects. Snapshot is stored on either network location or on the hard drive. You can define the interval to generate the snapshot using the SQL Job schedule. Read More
In this article, I am going to demonstrate how to create transactional replication.
Transactional replication generated a snapshot of publication DB objects and data within it. After the snapshot is generated, all the data changes and schema changes occurred on the publisher database are delivered to subscriber databases. In transactional replication, data and schema changes are almost real-time, hence transactional replication can be used to offloading reports and sometimes can be used as DR Site.
Using database maintenance plans, we can automate basic database administration activities. Maintenance plans are SQL Server integration service packages which are executed by SQL Server Agent job on configured schedule. Using maintenance plans, we can automate the following tasks.
- Shrink a database
- Backup a database
- Operator notification
- Update database statistics
- Perform database integrity check
- Execute SQL Server Agent jobs
- Execute T-SQL script
- Reorganize or rebuild indexes
Moreover, we can set up an alert to notify a DBA about the status of maintenance plan execution by enabling the Database Mail.
In this article, I am going to explain how to create a basic maintenance plan to perform database consistency check on a user database. Read More
SQL Server Database Mail has been introduced in SQL Server 2005. Database Mail is a component that can send emails using SQL Server Engine. Using Database Mail, an administrator or a developer can send query output to an end user. DBAs can configure it to get email alerts and notifications. Database Mail uses SMTP (Simple Mail Transfer Protocol) to deliver emails to recipients.
In this article, I am going to demonstrate how to configure SQL Server Database Mail. Read More
In my previous articles, I explained how to create and configure the FILESTREAM feature in SQL server instance. Moreover, I demonstrated how to create a table that has a FILESTREAM column and hot to insert and delete the data from it.
In this article, I am going to explain how to backup and restore the FILESTREAM-enabled dataase. Moreover, I am going to demonstrate how to restore FILESTREAM filegroup without making database offline. Read More
In my previous article, I described how to configure FILESTREAM in SQL Server, create FILESTREAM-enabled database and tables. Moreover, I demonstrated how to insert and delete data from the FILESTREAM table.
In this article, I am going to demonstrate how to insert multiple files in a FILESTREAM table using T-SQL. Read More
FILESTREAM has been introduced by Microsoft in 2008. The purpose was to store and manage unstructured files more effectively. Before FILESTREAM was introduced, the following approaches were used to store the data in SQL server:
- Unstructured files can be stored in the VARBINARY or IMAGE column of a SQL Server table. This approach is effective to maintain transactional consistency and reduces the file management complexity, but when the client application reads data from the SQL table, it uses SQL memory which leads to poor performance.
- Instead of storing the entire file in the SQL table, store the physical location of the unstructured file in SQL Table. This approach gives huge performance improvement, but it does not ensure the transactional consistency moreover file management was difficult too.