> where p.id_line=1
this filters rows after join was applied. Try this
select c.id_currency,max(p.modified_on) from currency c left join
price_line p using (id_currency) where (p.id_line=1 or p.id_line is null) group by
c.id_currency;
> Hi,
> This query:
> select c.id_currency,max(p.modified_on) from currency c left join
> price_line p using (id_currency) where p.id_line=1 group by
> c.id_currency;
> doesn't list all c.id_currency's, only those with a price_line. However
> this one does:
> select c.id_currency,max(p.modified_on) from currency c left join
> price_line p on (p.id_currency = c.id_currency and p.id_line=1) group by
> c.id_currency;
> How come?
> Thanks,
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