SQL - Converting char to exact length varchar

http://stackoverflow.com/questions/3110144/sql-converting-char-to-exact-length-varchar

I am trying to do something like this:

SELECT CAST(MYCHARCOL AS VARCHAR(LEN(MYCHARCOL))) 
FROM MYTABLE
SELECT CAST(MYCHARCOL AS VARCHAR(LEN(MYCHARCOL))) 
FROM MYTABLE

How do I convert a char column to varchar that is the exact length of the data inside that char column?

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You can't do that

Try this

SELECT CAST(RTRIM(MYCHARCOL) AS VARCHAR(8000)) FROM MYTABLE
SELECT CAST(RTRIM(MYCHARCOL) AS VARCHAR(8000)) FROM MYTABLE