On 2018/06/30 3:12 PM, Luuk wrote:
Ok ,my highway to hell start here (regargind the use of SQL)
In SQLite3 you are allowed to do this:
SELECT a,b,c
FROM t1
GROUP BY a
The values of 'b' and 'c' will be taken from a 'random' row...
But if we rewrite this in SQL, i am getting something like
On 30-6-2018 15:45, Luuk wrote:
>
> In SQLite3 you are allowed to do this:
> SELECT a,b,c
> FROM t1
> GROUP BY a
>
> The values of 'b' and 'c' will be taken from a 'random' row...
>
> But if we rewrite this in SQL, i am getting something like this:
> SELECT
>a,
>(SELECT MIN(b) FROM T1
If you want the row with the minimum B, and the row with a minimum C, then
the union of two queries would seem to be appropriate.
Gerry Snyder
On Sat, Jun 30, 2018, 6:45 AM Luuk wrote:
>
>
> On 30-6-2018 15:39, Abroży Nieprzełoży wrote:
> >> SELECT
> >>a,
> >>(SELECT MIN(b) FROM T1
>>> SELECT
>>>a,
>>>(SELECT MIN(b) FROM T1 WHERE a=t.a) AS B,
>>>(SELECT MIN(c) FROM T1 WHERE a=t.a) AS C
>>> FROM t1 t
>>> GROUP BY a
>> Why not
>> select a, min(b) as b, min(c) as c from t1 group by a;
>> ?
>
> It still does not quarantee that the valuse show for b and c are
On 30-6-2018 15:39, Abroży Nieprzełoży wrote:
>> SELECT
>>a,
>>(SELECT MIN(b) FROM T1 WHERE a=t.a) AS B,
>>(SELECT MIN(c) FROM T1 WHERE a=t.a) AS C
>> FROM t1 t
>> GROUP BY a
> Why not
> select a, min(b) as b, min(c) as c from t1 group by a;
> ?
It still does not quarantee that
> SELECT
>a,
>(SELECT MIN(b) FROM T1 WHERE a=t.a) AS B,
>(SELECT MIN(c) FROM T1 WHERE a=t.a) AS C
> FROM t1 t
> GROUP BY a
Why not
select a, min(b) as b, min(c) as c from t1 group by a;
?
2018-06-30 15:12 GMT+02:00, Luuk :
>
> On 30-6-2018 14:55, Keith Medcalf wrote:
>> Note
On 30-6-2018 14:55, Keith Medcalf wrote:
> Note that this is SQLite3 specific (and specific to Sybase of the era where
> Microsoft SQL Server was actually just a rebranded Sybase, and Microsoft
> re-writes of SQL Server up to about 2000). Technically you cannot do a query
> of the form:
>
>
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