How to Prevent Recursion in SQL Server Triggers?

Preventing Recursion in SQL Server Triggers

Triggers are a powerful tool in database management, allowing developers to implement custom actions when specific events occur in a database. However, triggers can also lead to unintended recursion, where a trigger calls itself, resulting in an infinite loop.

In SQL Server, triggers can be created to execute automatically when a table is modified through insert, update, or delete operations. To prevent recursion, it is crucial to implement a check within the trigger code to differentiate between updates initiated by the trigger itself and updates coming from other sources.

One approach to prevent recursion is to check the nesting level of the trigger using the TRIGGER_NESTLEVEL() function. This function returns the current nesting level of the trigger, indicating the number of times it has executed recursively. If the current nesting level is greater than 1, it indicates that the trigger is being executed from another trigger's action, and therefore no further action is necessary.

Here is the updated trigger code that incorporates this approach:

ALTER TRIGGER [dbo].[tblMediaAfterInsertOrUpdate] 
   ON  [dbo].[tblMedia]
   BEFORE INSERT, UPDATE
AS 
BEGIN
    SET NOCOUNT ON

    DECLARE @IdMedia INTEGER,
        @NewSubject NVARCHAR(200)   

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