SQL 2005 nvarchar(max) problem

I have the following in a stored procedure:

DECLARE @TSQL NVARCHAR(MAX)

SET @TSQL = N'.....' Which contains about 33000 characters of text

When I do a PRINT LEN(@TSQL) 7968 is returned. Why is the rest of @TSQL c开发者_StackOverflowut off?

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Make sure that when you concatenate everything is a nvarchar(max)

take a look at this

DECLARE @n NVARCHAR(MAX)
SELECT @n = REPLICATE(convert(varchar(max),'A'),300000)

select LEN(@n), DATALENGTH(@n)
GO

--300000 600000

DECLARE @n NVARCHAR(MAX)
SELECT @n = REPLICATE('A',300000)

select LEN(@n), DATALENGTH(@n)

--8000 16000