SQL Clone
SQLServerCentral is supported by Redgate
 
Log in  ::  Register  ::  Not logged in
 
 
 


Data Type and Length


Data Type and Length

Author
Message
Hugo Kornelis
Hugo Kornelis
SSChampion
SSChampion (10K reputation)SSChampion (10K reputation)SSChampion (10K reputation)SSChampion (10K reputation)SSChampion (10K reputation)SSChampion (10K reputation)SSChampion (10K reputation)SSChampion (10K reputation)

Group: General Forum Members
Points: 10981 Visits: 11986
David Data (9/28/2010)
OTOH I designed our ETL system with [Postcode] [nvarchar](10) and then had to change it when I found records with postcodes like 'If out please leave by back door or with neighbour at No. 127' Sad

I really hope your design change was to add a column for "delivery comments", not to increase the maximum length for the postcode. (Unless your business operates in a country where 'If out please leave by back door or with neighbour at No. 127' is a valid postcode).
But I do hope you changed the postcode to varchar(10). As far as I know, all countries in the world that use postal codes limit them to numbers and the letters A-Z.


Hugo Kornelis, SQL Server MVP
Visit my SQL Server blog: http://sqlblog.com/blogs/hugo_kornelis
Jeff Moden
Jeff Moden
SSC Guru
SSC Guru (85K reputation)SSC Guru (85K reputation)SSC Guru (85K reputation)SSC Guru (85K reputation)SSC Guru (85K reputation)SSC Guru (85K reputation)SSC Guru (85K reputation)SSC Guru (85K reputation)

Group: General Forum Members
Points: 85873 Visits: 41091
David Data (9/27/2010)
But I am curious as to why a VARCHAR(MAX) string that happens to contain say 100 chars is so much slower that a VARCHAR(100) that does? Its index and length values will have to be 32 bit numbers, but with 32/64 bit CPUs anything shorter tends to be less rather than more efficient anyway. As even a VARCHAR(100) is stored as a variable length string, I would not imagine the memory management issues are much different either. Or are they?


Im not sure. Some folks insist (and maybe rightfully so... I seem to remember such a thing in BOL but don't remember for sure) the VARCHAR(MAX) stays "inrow" under such conditions. To me, it seems like it may not but I've not taken the time to research that to any depth. It would be nice to know for sure but I just don't have the floor space on my dance card right now.

--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.
If you think its expensive to hire a professional to do the job, wait until you hire an amateur. -- Red Adair

Helpful Links:
How to post code problems
How to post performance problems
Forum FAQs
Go


Permissions

You can't post new topics.
You can't post topic replies.
You can't post new polls.
You can't post replies to polls.
You can't edit your own topics.
You can't delete your own topics.
You can't edit other topics.
You can't delete other topics.
You can't edit your own posts.
You can't edit other posts.
You can't delete your own posts.
You can't delete other posts.
You can't post events.
You can't edit your own events.
You can't edit other events.
You can't delete your own events.
You can't delete other events.
You can't send private messages.
You can't send emails.
You can read topics.
You can't vote in polls.
You can't upload attachments.
You can download attachments.
You can't post HTML code.
You can't edit HTML code.
You can't post IFCode.
You can't post JavaScript.
You can post emoticons.
You can't post or upload images.

Select a forum

































































































































































SQLServerCentral


Search