Is there any sort order if we don't use order by? for example,
select * from tablename
what is sort order? each time, I get the same records with the same order,
any mystery?As far as the I know, the order was the same as you add the data.
You can change the order bu add "order by" statement , I think you can get
whole information from BOL|||Wei
I don't think that order depends on insertion. (unless you have clustered
index on this column)
"Wei Ci Zhou" <weicizhou@.hotmail.com.discuss> wrote in message
news:O9uMAcW6DHA.2380@.TK2MSFTNGP10.phx.gbl...
quote:|||Hi ,
> As far as the I know, the order was the same as you add the data.
> You can change the order bu add "order by" statement , I think you can get
> whole information from BOL
>
If you have a clusted index in that table database will be ordered based on
the Index key. So incase if you have a clustered index the
"select * from tablename" will return the result set based on the clustered
index key order.
If you donot have a clusted index the result set will be reurned based on
the way you inserted.
Thanks
Hari
MCDBA
"John" <spam@.spam.com> wrote in message
news:OkuS1PW6DHA.1636@.TK2MSFTNGP12.phx.gbl...
quote:|||records are sorted in ascending order by default.
> Hi,
> Is there any sort order if we don't use order by? for example,
> select * from tablename
> what is sort order? each time, I get the same records with the same order,
> any mystery?
>
"John" <spam@.spam.com> wrote in message
news:OkuS1PW6DHA.1636@.TK2MSFTNGP12.phx.gbl...
quote:|||Sorry
> Hi,
> Is there any sort order if we don't use order by? for example,
> select * from tablename
> what is sort order? each time, I get the same records with the same order,
> any mystery?
>
quote:
> I don't think that order depends on insertion. (unless you have clustered
> index on this column)
I meant if you don't have a clustered index on the column it depends on
insertion.
"Uri Dimant" <urid@.iscar.co.il> wrote in message
news:#JxgijW6DHA.3548@.TK2MSFTNGP11.phx.gbl...
quote:|||The first reply you made me shocked
> Wei
> I don't think that order depends on insertion. (unless you have clustered
> index on this column)
>
> "Wei Ci Zhou" <weicizhou@.hotmail.com.discuss> wrote in message
> news:O9uMAcW6DHA.2380@.TK2MSFTNGP10.phx.gbl...
get[QUOTE]
>
|||> If you have a clusted index in that table database will be ordered based onquote:
> the Index key.
Not necessarily. See my other post.
Tibor Karaszi, SQL Server MVP
Archive at: http://groups.google.com/groups?oi=...ls
erver
"Hari Prasad" <hari_prasad_k@.hotmail.com> wrote in message
news:uPL7gkW6DHA.2628@.TK2MSFTNGP10.phx.gbl...
quote:|||> I meant if you don't have a clustered index on the column it depends on
> Hi ,
> If you have a clusted index in that table database will be ordered based o
n
> the Index key. So incase if you have a clustered index the
> "select * from tablename" will return the result set based on the clustere
d
> index key order.
> If you donot have a clusted index the result set will be reurned based on
> the way you inserted.
>
> Thanks
> Hari
> MCDBA
> "John" <spam@.spam.com> wrote in message
> news:OkuS1PW6DHA.1636@.TK2MSFTNGP12.phx.gbl...
>
quote:
> insertion.
Not correct. I'm afraid. See my other post.
Tibor Karaszi, SQL Server MVP
Archive at: http://groups.google.com/groups?oi=...ls
erver
"Uri Dimant" <urid@.iscar.co.il> wrote in message news:%23qCR2tW6DHA.1936@.TK2MSFTNGP12.phx.gbl...[Q
UOTE]
> Sorry
> I meant if you don't have a clustered index on the column it depends on
> insertion.
>
> "Uri Dimant" <urid@.iscar.co.il> wrote in message
> news:#JxgijW6DHA.3548@.TK2MSFTNGP11.phx.gbl...
> get
>[/QUOTE]|||A table, is in the relation model, an unordered set of rows. Imagine your ro
ws being notes on
paper-slips and you throw them into a bag. The back is shaken from time to t
ime. Now. try to pull
the paper-slips out of this bag "in order". The term "order" doesn't make se
nse in the relational
model.
To be more specific, if you don't have order by, the optimizer is free to re
turn the rows in any
order. It will pick the order it finds most cost-effective.
It doesn't have to be in the same sequence as the rows are inserted (read ab
out IAM page etc in the
physical database chapter in Books Online). That is regardless whether you h
ave a clustered index or
not.
It doesn't have to be in the same sequence as the clustered index. The index
can be heavy
fragmented, so the optimizer can decide to instead of jumping back and forth
on the disk, it will
scan the file in physical order, according to the IAM page.
Tibor Karaszi, SQL Server MVP
Archive at: http://groups.google.com/groups?oi=...ls
erver
"John" <spam@.spam.com> wrote in message news:OkuS1PW6DHA.1636@.TK2MSFTNGP12.phx.gbl...
quote:
[color
=darkred]
> Hi,
> Is there any sort order if we don't use order by? for example,
> select * from tablename
> what is sort order? each time, I get the same records with the same order,
> any mystery?
>[/color]
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