Should You Use 'SET NOCOUNT ON' in SQL Server?

The pros and cons of "SET NOCOUNT ON" in SQL Server

In SQL Server, the "SET NOCOUNT ON" command is used to suppress the "x rows affected" message that appears after executing a Data Manipulation Language (DML) statement. While this setting can provide certain benefits, it's important to understand its potential impact before using it.

Advantages of using "SET NOCOUNT ON":

• Reduce network bandwidth: Eliminating the "x rows affected" message can save a small amount of network bandwidth.
• Potential performance improvements: In some cases, such as forward-only cursors, suppressing row count calculations can improve performance.

Disadvantages of using "SET NOCOUNT ON":

• Compatibility Issue: "SET NOCOUNT ON" may cause errors in applications that rely on the "x rows affected" message, such as .NET SQLDataAdapters, Linq 2 SQL, and JPA.
• Lack of row count information: Without the "x rows affected" message, it is more difficult to verify the impact of DML statements, filter out trivial updates, and perform other tasks that require row count information.
• Trigger incompatibility: Using "SET NOCOUNT ON" in a trigger may cause problems with certain Object Relational Mapping (ORM) frameworks (such as nHibernate) and database tools (such as Microsoft SQL Server Management Studio). (SSMS)) an error occurred.

Recommendation:

Given the potential drawbacks, it is generally not recommended to use "SET NOCOUNT ON" as a general rule. Instead, it should be used with caution in specific situations where the performance advantages outweigh the compatibility issues.

It is recommended to avoid using "SET NOCOUNT ON" if compatibility with external applications is critical. However, "SET NOCOUNT ON" can be a useful optimization technique in situations where performance is a primary factor and compatibility issues do not exist.

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