RE: char(n) v varchar(n) - data type length question

SSC Guru

Points: 1003857

January 12, 2015 at 3:52 pm

As Lowell stated, LEN() will only return the number of characters in a string (with a caveat that I'll explain in a minute) whereas DATALENGTH will return the number of bytes in a string. Generally speaking, Unicode strings will have 2 bytes per character in SQL Server.

The caveat that I spoke of is that LEN() will NOT find/report on trailing spaces (and certain other characters) but DATALENGTH will whether of not it's a Unicode string or not.

--Jeff Moden

RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.

Change is inevitable... Change for the better is not.

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