Can I default a sql stored procedure parameter to a dynamic expression?

I want to have a "@myDate" parameter in a stored procedure that defaults to 2 years prior to today if nothing else is specified. I tried doing something like this in my procedure definition:

CREATE PROCEDURE myProcedure(   @param1 int,
                                @param2 varchar(20),
                                @param3 int = null,
                                @myDate datetime = dateadd(year,-2,getDate()) )
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I'm getting the following syntax error:

Incorrect syntax near '('.

Does sql server allow you to set dynamic expressions as default parameter values? If not, how can I get around this (other than the clumsy IF @myDate is null SET @myDate=...)?

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You can't use an expression as default value, and there is no really elegant way of doing this.

You can use isnull or coalesce instead of the if statement:

set @myDate = isnull(@myDate, dateadd(year, -2, getdate()))

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No.

From the docs:

The default value must be a constant or it can be NULL