On Wed, 19 Sep 2007 18:20:53 +0200, Kees Nuyt
<k.nuyt@nospam.demon.nl> wrote:

>On Tue, 18 Sep 2007 14:12:43 +0200, "Bob Bedford"
><bob@bedford.com> wrote:
>
>>Hi all,
>>
>>I've to return only 1 field with the minimum value coming from 2 tables:
>>
>>select min(table1.datetimex) as mindate1, min(table2.datetimex) as mindate2
>>from table1 left join table 2 on table1.id = table2.id where table1.id = 123
>>or table2.id = 123
>>
>>In fact I've to check the minimum date if a record has been created in
>>table1 or table2.
>>
>>I've tried min(table1.datetimex, table2.datetimex) as mindate but it doesn't
>>work.
>>
>>How can I do that ?
>>
>>Also if there is nothing in table1 and something in table2, do I have a
>>result ?
>
>Perhaps:
>SELECT min(datetimeex)
> FROM (
> SELECT id,datetimexe FROM table1
> UNION
> SELECT id,datetimexe FROM table2
>) WHERE id = 123;
>
>?

Or (probably more efficient):
SELECT min(datetimeex)
FROM (
SELECT id,datetimexe FROM table1 WHERE id = 123
UNION
SELECT id,datetimexe FROM table2 WHERE id = 123
);


>>Thanks for helping
>>
>>Bob
--
( Kees
)
c[_] Truck Pulls: for people who cannot understand the WWF (#371)