您的代码按预期运行.该过程递归地调用自己.

Your code is behaving as expected. The procedure is calling itself recursively.

如果你不想要那样，试试这个:

If you do not want that, try this:

ALTER PROCEDURE dbo.Test 
    @Value int = null

AS

BEGIN

    IF (IsNull(@Value, '') = '')
        SELECT 'I am NULL!'
    ELSE
        SELECT 'I am ' + CONVERT(varchar(20), @Value)

END

GO

EXEC dbo.Test

如果你确实想使用递归，你必须定义一个基本案例(又名退出条件")，这将使存储过程退出递归堆栈.

If you do want to use recursion, you have to define a base case (AKA "exit condition") which will make stored procedure exit the recursion stack.