Sum of Two Union Queries

[Brent Wege]

Hi I have the following union query that retrieves two counts. Can I
sum them up within this query, like wrap this in a sum function
somehow to get the total count? Or is there a better way to do this.
Please help. Using SQL 2000.



select count(user_id) from table1

UNION

select count(user_id) from table2

[Steve Kass]

Re: Sum of Two Union Queries

Brent,

First, I'm guessing you don't really
mean UNION here. If you did, you would
get

----------
40

from your query if by chance each of table1
and table2 contained 40 rows each with non-null
user_id values.

Because you mention UNION, I'm not sure whether
you might want the total count of unique user_id
values from the two tables, or just the sum of
the counts.

If you want the latter, just the sum of the counts,
here is a possibility:

select
(select count(user_id) from table1)
+ (select count(user_id) from table2)
as totalCount

If you need to count user_id values only once when
they appear in both table1 and table2, you can do this:

select count(user_id)
from (
select user_id from table1
union
select user_id from table2
) T

-- Steve Kass
-- Drew University
-- Ref: 68959432-090F-4058-8185-BE7DA62CBE6A



Brent Wege wrote:[color=blue]
> Hi I have the following union query that retrieves two counts. Can I
> sum them up within this query, like wrap this in a sum function
> somehow to get the total count? Or is there a better way to do this.
> Please help. Using SQL 2000.
>
>
>
> select count(user_id) from table1
>
> UNION
>
> select count(user_id) from table2[/color]

[Brent Wege]

Re: Sum of Two Union Queries

This helps a lot... thanks!

Steve Kass <skass@drew.edu > wrote in message news:<eTtbb.530 93$NM1.7813@new sread2.news.atl .earthlink.net> ...[color=blue]
> Brent,
>
> First, I'm guessing you don't really
> mean UNION here. If you did, you would
> get[/color]