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Home -> Community -> Mailing Lists -> Oracle-L -> RE: empty string = null?
I feel I had the same dream. Anyway this from Oracle 9i doc:
Nulls
"If a column in a row has no value, then the column is said to be null, or
to contain a null. Nulls can appear in columns of any datatype that are not
restricted by NOT
NULL or PRIMARY KEY integrity constraints. Use a null when the actual value
is not known or when a value would not be meaningful.
Do not use null to represent a value of zero, because they are not
equivalent. (Oracle currently treats a character value with a length of zero
as null. However, this
may not continue to be true in future releases, and Oracle recommends that
you do not treat empty strings the same as nulls.) Any arithmetic expression
containing a
null always evaluates to null. For example, null added to 10 is null. In
fact, all operators (except concatenation) return null when given a null
operand."
Regards,
Waleed
-----Original Message-----
<mailto:listmail_at_gennick.com> ]
Sent: Thursday, April 11, 2002 8:44 PM
To: Multiple recipients of list ORACLE-L
Oracle has always treated empty strings (e.g.: '') as nulls. As I sit here and think about this, I can convince myself that I read somewhere that Oracle9i provided an option to treat empty strings not as nulls, but truly as empty strings. Is this the case, or is my mind manufacturing memories?
Jonathan Gennick --- Brighten the corner where you are mailto:jonathan_at_gennick.com <mailto:jonathan_at_gennick.com>
http://Gennick.com <http://Gennick.com> * http://MichiganWaterfalls.com
-- Please see the official ORACLE-L FAQ: http://www.orafaq.comReceived on Thu Apr 11 2002 - 20:33:18 CDT
<http://www.orafaq.com>
-- Author: Jonathan Gennick INET: listmail_at_gennick.com Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Khedr, Waleed INET: Waleed.Khedr_at_FMR.COM Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
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