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String Length


String Length

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paul.knibbs
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Hugo Kornelis (7/11/2012)
In my opinion, it is LEN() that has the strange behaviour here, because it returns the length of the padded version of the string instead of the length of the string itself.


Well, it's strange behaviour of LEN() when you provide it with an NCHAR parameter, which is what I sort of meant but failed to express in any comprehensible manner... :-)
(Bob Brown)
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Great question. Tests some basics that sometimes trips us up.
Michael Lysons
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Nice one. I learned some new stuff today. :-)
IowaDave
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Why does datalength of nchar(40) give 80?!?? That really threw me.

Thanks!
paul.knibbs
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IowaDave (7/11/2012)
Why does datalength of nchar(40) give 80?!?? That really threw me.

Thanks!


Because the "n" means the string is Unicode, so it has two bytes per character; DATALENGTH returns the actual length of the storage used for the field. 2 bytes per character * 40 characters = 80 bytes.
Ken Wymore
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IowaDave (7/11/2012)
Why does datalength of nchar(40) give 80?!?? That really threw me.

Thanks!

Because it is the entire length of the string * 2 bytes. Nchar includes padding so the length is 40 versus 7 with nvarchar which does not include padding.
Dana Medley
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Thanks for the great question. I was actually brushing up on len() and datalength() just a couple of days ago so it was still really fresh on my brain. :-D



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DugyC
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Great question Kenneth, refreshed the old memory banks there ;-)

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thanks for the question.

Jason...AKA CirqueDeSQLeil
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Good question!


Sujeet Singh
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