How to store Zero length strings, numbers, dates?

I am used to storing Null when a value does not exist. I have been told to
store "zero length strings" in some cases instead. Fine . . .
I do not know how to generate a "zero length string" or a "zero length
number" or anything else "zero length." But I suspect it is simple. Can you
provide a few simple examples?
Thanks
Michaelset columnName = '' (that's 2 single quotes)
for a zero length string.
If the column is a character data type, no problem.
If it's an Int though, the column will return a 0, not necessarily what you
want.
"Snake" <Snake@.discussions.microsoft.com> wrote in message
news:60BEB714-6B32-473A-8CD6-9036620F3892@.microsoft.com...
>I am used to storing Null when a value does not exist. I have been told to
> store "zero length strings" in some cases instead. Fine . . .
> I do not know how to generate a "zero length string" or a "zero length
> number" or anything else "zero length." But I suspect it is simple. Can
> you
> provide a few simple examples?
> Thanks
> Michael
>|||Why are you told to store zero length string? Null is a perfectly good value
especially for cases where the value is unknown.
Anyway, zero length is equivalent to "".
e.g.
create table tb(abc varchar(10) not null)
insert tb values('abc')
insert tb values('')
insert tb values('def')
-oj
"Snake" <Snake@.discussions.microsoft.com> wrote in message
news:60BEB714-6B32-473A-8CD6-9036620F3892@.microsoft.com...
>I am used to storing Null when a value does not exist. I have been told to
> store "zero length strings" in some cases instead. Fine . . .
> I do not know how to generate a "zero length string" or a "zero length
> number" or anything else "zero length." But I suspect it is simple. Can
> you
> provide a few simple examples?
> Thanks
> Michael
>|||I prefer storing Nulls, but that's me. An empty string is typically designat
ed
by two single quotes like so:
Create Table Foo
(
Bar VarChar(10)
)
Insert Foo (Bar) Values('')
There is no such thing as a "zero length number." If the value is a number,
then
it must have a numerical representation or be null. There is nothing in betw
een.
If the value is a string that has a number in it (e.g. '0' as opposed to 0),
then it is obviously the rules above apply.
Thomas
"Snake" <Snake@.discussions.microsoft.com> wrote in message
news:60BEB714-6B32-473A-8CD6-9036620F3892@.microsoft.com...
>I am used to storing Null when a value does not exist. I have been told to
> store "zero length strings" in some cases instead. Fine . . .
> I do not know how to generate a "zero length string" or a "zero length
> number" or anything else "zero length." But I suspect it is simple. Can y
ou
> provide a few simple examples?
> Thanks
> Michael
>|||Another thing:
A zero length string in a date column will also not work as you think.
"Raymond D'Anjou" <rdanjou@.savantsoftNOSPAM.net> wrote in message
news:%23T4$yKOTFHA.2680@.tk2msftngp13.phx.gbl...
> set columnName = '' (that's 2 single quotes)
> for a zero length string.
> If the column is a character data type, no problem.
> If it's an Int though, the column will return a 0, not necessarily what
> you want.
> "Snake" <Snake@.discussions.microsoft.com> wrote in message
> news:60BEB714-6B32-473A-8CD6-9036620F3892@.microsoft.com...
>|||Null is a perfectly good value *only* for cases where the value is unknown
:)
The OP said that he was told to store zero-length strings in "some cases
instead." This tells me that in some instances they recognize that the
value is not "unknown", but rather is is "known to be nothing".
Middle names are a perfect example. If you don't know someone's middle
name, you could use NULL to indicate it is unknown. If you know that the
person has *no* middle name, you could use '' to indicate that this person
has no middle name, and that you recognize this fact.
"oj" <nospam_ojngo@.home.com> wrote in message
news:%23$IbhMOTFHA.3544@.TK2MSFTNGP12.phx.gbl...
> Why are you told to store zero length string? Null is a perfectly good
> value especially for cases where the value is unknown.
> Anyway, zero length is equivalent to "".
> e.g.
> create table tb(abc varchar(10) not null)
> insert tb values('abc')
> insert tb values('')
> insert tb values('def')
> --
> -oj
>
> "Snake" <Snake@.discussions.microsoft.com> wrote in message
> news:60BEB714-6B32-473A-8CD6-9036620F3892@.microsoft.com...
>|||He also says that they want to store zero-length strings in numeric and date
columns.
That one I really don't get.
Even if you could store it, what would a zero-length string mean in these
cases?
"Michael C#" <howsa@.boutdat.com> wrote in message
news:%235Ak%23UOTFHA.3280@.TK2MSFTNGP09.phx.gbl...
> Null is a perfectly good value *only* for cases where the value is unknown
> :)
> The OP said that he was told to store zero-length strings in "some cases
> instead." This tells me that in some instances they recognize that the
> value is not "unknown", but rather is is "known to be nothing".
> Middle names are a perfect example. If you don't know someone's middle
> name, you could use NULL to indicate it is unknown. If you know that the
> person has *no* middle name, you could use '' to indicate that this person
> has no middle name, and that you recognize this fact.
>
> "oj" <nospam_ojngo@.home.com> wrote in message
> news:%23$IbhMOTFHA.3544@.TK2MSFTNGP12.phx.gbl...
>|||Some people store dates in CHAR columns. Not something I would recommend,
but to each his/her own. The only other way around storing NULLs in numeric
and DATETIME columns would be to define a value that is out of range for
your purposes. For instance "9999-12-31" for an out of range date. Of
course then you introduce the Y10K problem which will have your great,
great, great, great, great (x 100's) grandchildren pulling out their hair
and cursing the day you were born...
"Raymond D'Anjou" <rdanjou@.savantsoftNOSPAM.net> wrote in message
news:e$MCzbOTFHA.2424@.TK2MSFTNGP09.phx.gbl...
> He also says that they want to store zero-length strings in numeric and
> date columns.
> That one I really don't get.
> Even if you could store it, what would a zero-length string mean in these
> cases?
> "Michael C#" <howsa@.boutdat.com> wrote in message
> news:%235Ak%23UOTFHA.3280@.TK2MSFTNGP09.phx.gbl...
>|||I would like to thank everyone who responded!
The individual who told me store "zero length strings" feels this "saves
space" and is "more efficient" than storing NULL. I know there are
length-indiocators and Null-indicators stored on the database page but I
don't exactly know their behaviors. My position has always been that storin
g
NULL is way less than 1% of the space normally used by data, so don't worry
about it. Am I overlooking something "material?"
Michael
"oj" wrote:

> Why are you told to store zero length string? Null is a perfectly good val
ue
> especially for cases where the value is unknown.
> Anyway, zero length is equivalent to "".
> e.g.
> create table tb(abc varchar(10) not null)
> insert tb values('abc')
> insert tb values('')
> insert tb values('def')
> --
> -oj
>
> "Snake" <Snake@.discussions.microsoft.com> wrote in message
> news:60BEB714-6B32-473A-8CD6-9036620F3892@.microsoft.com...
>
>|||zero-length neurons?
"Raymond D'Anjou" wrote:

> He also says that they want to store zero-length strings in numeric and da
te
> columns.
> That one I really don't get.
> Even if you could store it, what would a zero-length string mean in these
> cases?
> "Michael C#" <howsa@.boutdat.com> wrote in message
> news:%235Ak%23UOTFHA.3280@.TK2MSFTNGP09.phx.gbl...
>
>