Posted by Tom Moreau on 04/26/06 13:57

Order is not guaranteed unless you include an ORDER BY. This is by design.

--
Tom

----------------------------------------------------
Thomas A. Moreau, BSc, PhD, MCSE, MCDBA
SQL Server MVP
Toronto, ON Canada
..
"John Rivers" <first10@btinternet.com> wrote in message
news:1146048739.469710.138210@e56g2000cwe.googlegroups.com...
Hello,

if you create this table:

create table hello (
int a
, int b
constraint pk_hello primary key clustered ( a, b )
)

and then insert the following records

a,b
1,1
1,2
1,3
2,1
2,2
2,3
3,1
3,2
3,3

and then do

select a,b from hello

the output seems to be:

a,b
1,1
2,1
3,1
1,2
2,2
3,2
1,3
2,3
3,3

which is wrong and (i think) is reflecting the actual index order
and physical order on disk

it should be:

a,b
1,1
1,2
1,3
2,1
2,2
2,3
3,1
3,2
3,3

i have tested this on a table with 500,000 records

and sure enough if you declare the clustered primary key fields in
reverse order:

constraint pk_hello primary key clustered ( b, a )

two things happen:

- the select with no order by returns the records in the expected order
- queries relying on that order run MUCH FASTER

has anyone else seen / noticed this?

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