sql count(distinct(empid)) help

[unknown]

this works fine, returns count quickly:

select count(distinct(empid)) as eecount
from pr_detail_view

whereas this does not, at least quickly, I've never waited
until it finished, if it ever would...

select eefile.eecount
from (select count(distinct(empid)) as eecount
from pr_detail_view) eefile

What am I doing wrong? Why the performance hit? Thanks....

[Terry Dykstra [TeamSybase]]

That's a question for your DBMS vendor.
--
Terry Dykstra (TeamSybase)
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Post by unknown
select count(distinct(empid)) as eecount
from pr_detail_view
whereas this does not, at least quickly, I've never waited
until it finished, if it ever would...
select eefile.eecount
from (select count(distinct(empid)) as eecount
from pr_detail_view) eefile
What am I doing wrong? Why the performance hit? Thanks....