On Mar 3, 2009, at 3:26 PM, Emi Lu wrote:
Good morning,
Would it be possible to know that whether "union" is quicker than
"left join" in a general sense?
Queries:
(1) union
select a.*, b.value
from a
left join b
union
select a.*, c.value
from a
left joi
Good morning,
Would it be possible to know that whether "union" is quicker than "left
join" in a general sense?
Queries:
(1) union
select a.*, b.value
from a
left join b
union
select a.*, c.value
from a
left join c
(2) left join
select distinct a.*,
ca
