I'd like to use uniqueidentifier in my database as Primary Key
Is this a good idea?
How does it effect performance?
Plz help
ApogeeDo you mean a GUID? If so I would think this is quite a long field for a
primary key to be based on.
If you do use it, and you are generating a random one every time, I would
make sure the index isn't clustered, because you won't be inserting to the
bottom of the table.
"Apogee" <developer@.bitefish.net> wrote in message
news:exmBzrbUDHA.1680@.tk2msftngp13.phx.gbl...
> I'd like to use uniqueidentifier in my database as Primary Key
> Is this a good idea?
> How does it effect performance?
> Plz help
> Apogee
>|||What disadvantages would this have? (not clustered)
Apogee
"Ryan Breakspear" <r.breakspear@.removespamfdsltd.co.uk> wrote in message
news:eeHKXxbUDHA.1692@.TK2MSFTNGP11.phx.gbl...
> Do you mean a GUID? If so I would think this is quite a long field for a
> primary key to be based on.
> If you do use it, and you are generating a random one every time, I would
> make sure the index isn't clustered, because you won't be inserting to the
> bottom of the table.
> "Apogee" <developer@.bitefish.net> wrote in message
> news:exmBzrbUDHA.1680@.tk2msftngp13.phx.gbl...
> > I'd like to use uniqueidentifier in my database as Primary Key
> >
> > Is this a good idea?
> > How does it effect performance?
> >
> > Plz help
> >
> > Apogee
> >
> >
>|||I don't know a huge amount about this subject but I believe using a
clustered index, the data is actually stored in the order of the index. A
clustered index is therefore the fastest type. A non clustered is a normal
index, which contains the information you have included in your index, and
also a link to where the actual record is stored.
If you insert lots of records in the middle of a clustered index, the server
will have to do a certain amount or re-jigging of the data to keep it in the
actual order of the primary key.
I would suggest using a clustered index if you are using an auto increment
primary key, and a non clustered index if you are inserting random values.
If the tables are small, or without much activity, this is largely
irrelevant though.
Ryan
"Apogee" <developer@.bitefish.net> wrote in message
news:Oi88I%23bUDHA.2200@.TK2MSFTNGP11.phx.gbl...
> What disadvantages would this have? (not clustered)
> Apogee
>
> "Ryan Breakspear" <r.breakspear@.removespamfdsltd.co.uk> wrote in message
> news:eeHKXxbUDHA.1692@.TK2MSFTNGP11.phx.gbl...
> > Do you mean a GUID? If so I would think this is quite a long field for
a
> > primary key to be based on.
> >
> > If you do use it, and you are generating a random one every time, I
would
> > make sure the index isn't clustered, because you won't be inserting to
the
> > bottom of the table.
> >
> > "Apogee" <developer@.bitefish.net> wrote in message
> > news:exmBzrbUDHA.1680@.tk2msftngp13.phx.gbl...
> > > I'd like to use uniqueidentifier in my database as Primary Key
> > >
> > > Is this a good idea?
> > > How does it effect performance?
> > >
> > > Plz help
> > >
> > > Apogee
> > >
> > >
> >
> >
>|||I don't like using a GUID for an artificial primary key. It takes up 4 times
as much space as an int (16 bytes vs 4 bytes), and as the primary key is
referenced in other tables and indexes, this can add up to a large amount of
unnecessary space in your database, negatively impacting performance. You
can store more than 2 billion rows in a table when you have a IDENTITY
column starting at 1 with an INT datatype, and that is enough for most
applications. If it isn't you can always use a BIGINT (8 bytes) datatype.
Using GUIDs also makes debugging more difficult than using identity, because
humans are better at remembering 1-2-3 than at remembering 32 character
hexadecimal strings. And with IDENTITY the inserts are generated in order,
which can help debugging as well.
--
Jacco Schalkwijk MCDBA, MCSD, MCSE
Database Administrator
Eurostop Ltd.
"Apogee" <developer@.bitefish.net> wrote in message
news:exmBzrbUDHA.1680@.tk2msftngp13.phx.gbl...
> I'd like to use uniqueidentifier in my database as Primary Key
> Is this a good idea?
> How does it effect performance?
> Plz help
> Apogee
>
