Обсуждение: select where expr in - result order?

Is there any way to guarantee that the when using
SELECT * FROM tbl WHERE expr IN (scalar[,...])
the results are returned in the same order as the scalar list?

I realize I can do this by sorting the scalar list and using ORDER BY expr,
but I'd like to not count on a sorted list of scalars if at all possible.

thx
andy

"Andy Kriger" <akriger@greaterthanone.com> writes:

> Is there any way to guarantee that the when using
> SELECT * FROM tbl WHERE expr IN (scalar[,...])
> the results are returned in the same order as the scalar list?
>
> I realize I can do this by sorting the scalar list and using ORDER BY expr,
> but I'd like to not count on a sorted list of scalars if at all possible.

Nope, I'm pretty sure ORDER BY is the only way to do this.  SQL
queries don't in general guarantee any ordering unless an ORDER BY
clause is used.

-Doug

Doug McNaught wrote:
> "Andy Kriger" <akriger@greaterthanone.com> writes:
>
>
>>Is there any way to guarantee that the when using
>>SELECT * FROM tbl WHERE expr IN (scalar[,...])
>>the results are returned in the same order as the scalar list?
>>
>>I realize I can do this by sorting the scalar list and using ORDER BY expr,
>>but I'd like to not count on a sorted list of scalars if at all possible.
>
>
> Nope, I'm pretty sure ORDER BY is the only way to do this.  SQL
> queries don't in general guarantee any ordering unless an ORDER BY
> clause is used.
>
> -Doug
>
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