Hi,
I'm trying to decide whether I should use Guid.NewGuid() to generate an ID
or using database sequence. Is Guid.NewGuid() will return a unique number?
The MSDN said that the probability of duplication is low, but how low? Does
anyone know?
thanks,
/m
5  5179 
Hi muscha,
Unbelievably low - in fact low enough to basically be ignored. It is hard to
comprehend how large 128 bit integers actually are.
HTH,
--
Greg Low (MVP)
MSDE Manager SQL Tools www.whitebearconsulting.com
"muscha" <mu****@no.spam .net> wrote in message
news:O$******** ******@TK2MSFTN GP09.phx.gbl... Hi,
I'm trying to decide whether I should use Guid.NewGuid() to generate an ID
or using database sequence. Is Guid.NewGuid() will return a unique number?
The MSDN said that the probability of duplication is low, but how low?
Does anyone know?
thanks,
/m
> Unbelievably low - in fact low enough to basically be ignored. It is hard
to comprehend how large 128 bit integers actually are.
So is this a good practice? To use Guid as my ID generator?
thanks,
/m
HTH,
--
Greg Low (MVP)
MSDE Manager SQL Tools
www.whitebearconsulting.com
"muscha" <mu****@no.spam .net> wrote in message
news:O$******** ******@TK2MSFTN GP09.phx.gbl... Hi,
I'm trying to decide whether I should use Guid.NewGuid() to generate an
ID or using database sequence. Is Guid.NewGuid() will return a unique
number? The MSDN said that the probability of duplication is low, but how low?
Does anyone know?
thanks,
/m
I believe that duplications are not even possible, as long as you have a network card on the computer.
From what I understand, Guid's are generated based on the network card mac address as well as System ticks..
--------------
Robert Jeppesen
robert.jeppesen %at%durius-dot-se
"muscha" <mu****@no.spam .net> wrote in message news:O1******** ******@TK2MSFTN GP12.phx.gbl... Unbelievably low - in fact low enough to basically be ignored. It is hard
to comprehend how large 128 bit integers actually are.
So is this a good practice? To use Guid as my ID generator?
thanks,
/m
HTH,
--
Greg Low (MVP)
MSDE Manager SQL Tools
www.whitebearconsulting.com
"muscha" <mu****@no.spam .net> wrote in message
news:O$******** ******@TK2MSFTN GP09.phx.gbl... Hi,
I'm trying to decide whether I should use Guid.NewGuid() to generate an ID or using database sequence. Is Guid.NewGuid() will return a unique number? The MSDN said that the probability of duplication is low, but how low?
Does anyone know?
thanks,
/m
"Robert Jeppesen" <robert.jeppese n(#)durius.se> wrote in message
news:uL******** ******@TK2MSFTN GP09.phx.gbl... I believe that duplications are not even possible, as long as you have a
network card on the computer. From what I understand, Guid's are generated based on the network card mac
address as well as System ticks..
So .. no two computer should ever generate the same Guid yes? I am working
in multiple box setup and the uniqueness of the Guid is critical. This is
why we are thinking of using database sequence for the guarantee.
thanks,
/m
--------------
Robert Jeppesen
robert.jeppesen %at%durius-dot-se
"muscha" <mu****@no.spam .net> wrote in message
news:O1******** ******@TK2MSFTN GP12.phx.gbl... Unbelievably low - in fact low enough to basically be ignored. It is
hard to comprehend how large 128 bit integers actually are.
So is this a good practice? To use Guid as my ID generator?
thanks,
/m
HTH,
--
Greg Low (MVP)
MSDE Manager SQL Tools
www.whitebearconsulting.com
"muscha" <mu****@no.spam .net> wrote in message
news:O$******** ******@TK2MSFTN GP09.phx.gbl...
> Hi,
>
> I'm trying to decide whether I should use Guid.NewGuid() to generate
an ID > or using database sequence. Is Guid.NewGuid() will return a unique
number? > The MSDN said that the probability of duplication is low, but how
low? Does
> anyone know?
>
> thanks,
>
> /m
>
>
Globally Unique IDentifier says it all to me. Use GUIDs.
"muscha" <mu****@no.spam .net> wrote in message
news:eL******** ******@TK2MSFTN GP11.phx.gbl... "Robert Jeppesen" <robert.jeppese n(#)durius.se> wrote in message
news:uL******** ******@TK2MSFTN GP09.phx.gbl... I believe that duplications are not even possible, as long as you have a network card on the computer. From what I understand, Guid's are generated based on the network card
mac address as well as System ticks..
So .. no two computer should ever generate the same Guid yes? I am working
in multiple box setup and the uniqueness of the Guid is critical. This is
why we are thinking of using database sequence for the guarantee.
thanks,
/m
--------------
Robert Jeppesen
robert.jeppesen %at%durius-dot-se
"muscha" <mu****@no.spam .net> wrote in message news:O1******** ******@TK2MSFTN GP12.phx.gbl... > Unbelievably low - in fact low enough to basically be ignored. It is hard to
> comprehend how large 128 bit integers actually are.
So is this a good practice? To use Guid as my ID generator?
thanks,
/m
>
> HTH,
>
>
> --
> Greg Low (MVP)
> MSDE Manager SQL Tools
> www.whitebearconsulting.com
>
> "muscha" <mu****@no.spam .net> wrote in message
> news:O$******** ******@TK2MSFTN GP09.phx.gbl...
> > Hi,
> >
> > I'm trying to decide whether I should use Guid.NewGuid() to
generate an ID
> > or using database sequence. Is Guid.NewGuid() will return a unique
number?
> > The MSDN said that the probability of duplication is low, but how low? > Does
> > anyone know?
> >
> > thanks,
> >
> > /m
> >
> >
>
>
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