Null Vs. Empty in Webmasters and Developers http://www.dslreports.com/forum/r21754656 en Wed, 02 Dec 2009 23:42:04 EDT Wed, 02 Dec 2009 23:42:04 EDT Re: Null Vs. Empty http://www.dslreports.com/forum/remark,21761383 Tenar : Just don't set your database fields to 'NULL' (the string) LOL I've seen that. =P]]> http://www.dslreports.com/forum/remark,21761383 Sat, 17 Jan 2009 23:55:08 EDT Re: Null Vs. Empty http://www.dslreports.com/forum/remark,21759029 teddy : Just like to chip in, Oracle treats null and '' both as null. A pain sometimes, really.
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»www.chemicalfusion.net]]> http://www.dslreports.com/forum/remark,21759029 Sat, 17 Jan 2009 15:09:09 EDT Re: Null Vs. Empty http://www.dslreports.com/forum/remark,21755630 Code_Iain : Both other posters are correct with what they said, but just to give you an additional warning when working with both,

NULL represents the absence of a value and '' (empty string) is a value, so for example if your table has a unique index on a column, multiple rows can have that column set to NULL, but only 1 can be set to ''.]]> http://www.dslreports.com/forum/remark,21755630 Fri, 16 Jan 2009 20:45:19 EDT Re: Null Vs. Empty http://www.dslreports.com/forum/remark,21754842 McSummation : jayco437 See Profile did a good job of explaining the difference.

Another way to look at it is: a NULL field (can be any field, not just strings) has nothing stored in it. However, an "empty string" has a value, a "zero length" string.]]> http://www.dslreports.com/forum/remark,21754842 Fri, 16 Jan 2009 18:30:51 EDT Re: Null Vs. Empty http://www.dslreports.com/forum/remark,21754734 jayco437 :
said by squatpuke See Profile :

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If a database field is originally NULL...then data is added....then removed....is the field NULL again...
I would imagine it could vary between databases, but my general thought is no it would not be NULL unless you explicitly set it to NULL, versus setting it to a blank string.

said by squatpuke See Profile :

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What is the difference between NULL and Once Filled/Now Empty....
NULL is usually a default value for a field that doesn't require a value. Depending on the database, you could set default to an empty string instead of NULL. You could also programmatically set a field to NULL when it has been emptied of data, thus eliminating the ambiguity between NULL and and an empty string.]]> http://www.dslreports.com/forum/remark,21754734 Fri, 16 Jan 2009 18:10:46 EDT Null Vs. Empty http://www.dslreports.com/forum/remark,21754656 squatpuke : .
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If a database field is originally NULL...then data is added....then removed....is the field NULL again...

What is the difference between NULL and Once Filled/Now Empty....

Thanks...

(btw...TSql)]]> http://www.dslreports.com/forum/remark,21754656 Fri, 16 Jan 2009 17:53:28 EDT