Re: why use CHAR.. _EVER_?

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I just don't see the point in having 20 fields that are all varchar(50)
when they only hold data that is 10 characters long.

stuff like keys?

i personally think that all keys everywhere should always be an
integer-- or preferably smallint--


it just drives me crazy; i've noted some definite peculiarities


like i've got field1 = 'aaron ' stored in a table; if i search
using a query where field1 = 'aaron' it finds a match; is this
implicit?

does it automatically do a right trim on everything you do in a char
field?

i just dont understand why 'aaron' matches to 'aaron '

it just seems inconsistent the way that they do it.

-Aaron




Russ Rose wrote:
<dbahooker@xxxxxxxxxxx> wrote in message
news:1159570979.959302.321990@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
can someone list some good reasons for using CHAR?

i mean seriously here.
I've got this 3rd party database that's got EVERY SINGLE TEXT FIELD
uses CHAR instead of VarChar.

it's slow as a dog..

does anyone know why ANYONE EVER USERS CHAR?


The funniest thing I have ever seen in a database design is a bunch of
varchar(1) columns...

When a column is a fixed width it is easier for a seek algorithm to find the
data within a row, which is why is is best to have variable length columns
at the end of the table.

Fixed length columns are best for data that will hold a required value of a
specific length. The best example of this is ZIPCode (not postal code) where
it is always 5 characters and you want to preserve any leading 0's.

I doubt the difference between char and varchar is the reason for your
performance issue.

.

Relevant Pages

  • Re: why use CHAR.. _EVER_?
    ... when they only hold data that is 10 characters long. ... stuff like keys? ... using a query where field1 = 'aaron' it finds a match; ... SQL, by definition, ignores white-space at the end of CHAR data types. ...
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  • Re: why use CHAR.. _EVER_?
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