Raiserror with Nowait - SQL

Raiserror with Nowait is a SQL Server feature that allows developers to send error messages to a client immediately, rather than waiting for the entire batch to complete. This is useful when dealing with large batches of data or when real-time error messages are required.

Syntax

The syntax for Raiserror with Nowait is as follows:

RAISERROR ('message', severity, state) WITH NOWAIT

• message: The error message to be sent to the client.

• severity: The severity of the error, ranging from 1 to 25. The higher the severity, the more critical the error.

• state: An integer value that can be used to group errors. The value should be between 0 and 255.

Example

RAISERROR ('Invalid input', 16, 1) WITH NOWAIT

In the above example, an error message with severity level 16 is sent to the client immediately, with the message "Invalid input".

Considerations

When using Raiserror with Nowait, it's important to consider the following:

• The error message is sent to the client immediately, which may result in a flood of messages if not properly controlled.

• Raiserror with Nowait only works with client applications that support the "set nocount on" option.

• Raiserror with Nowait can only be used in the same session in which it was raised. If the session is closed, the message is lost.

Conclusion

Raiserror with Nowait is a powerful feature in SQL Server that enables developers to send real-time error messages to their clients. When used properly, it can greatly improve the user experience by providing immediate feedback on errors.