Hello with this query I'm getting one result with four rows, how can I change it in order to get four named columns with their own result every one?
SELECT COUNT(*) FROM vehicles WHERE cus=1
UNION ALL
SELECT COUNT(*) FROM user WHERE cus=1
UNION ALL
SELECT COUNT(*) FROM vehicle_events WHERE cus=1
UNION ALL
SELECT COUNT(*) FROM vehicle_alerts WHERE cus=1
Thanks in advance.
SELECT a.ct veh_count, b.ct user_count, c.ct event_count, d.ct alert_count
FROM
( SELECT COUNT(*) ct FROM vehicles WHERE cus=1 ) a,
( SELECT COUNT(*) ct FROM user WHERE cus=1 ) b,
( SELECT COUNT(*) ct FROM vehicle_events WHERE cus=1 ) c,
( SELECT COUNT(*) ct FROM vehicle_alerts WHERE cus=1 ) d;
UNION only adds rows; it has no effect on the columns.
Columns, which define the "shape" of the row tuples, must appear as selected columns1.
For example:
SELECT
(SELECT COUNT(*) FROM vehicles WHERE cus=1) as veh_count
,(SELECT COUNT(*) FROM users WHERE cus=1) as user_count
..
1 There are other constructs that can allow this, see crosstab for example - but the columns are fixed by the query command. It takes dynamic SQL to get a variable number of columns.
Related
I have two table with same name in two different schemas (old and new dump). I would like to know the difference between the two integration.
I have two queries, that gives old and new count:
select count(*) as count_old from(
SELECT
distinct id
FROM
schema1.compound)q1
select count(*) as count_new from(
SELECT
distinct id
FROM
schema2.compound)q2
I would like have the following output.
table_name count_new count_new diff
compound 4740 4735 5
Any help is appreciated. Thanks in advance
with counts as (
select
(select count(distinct id) from schema1.compound) as count_old,
(select count(distinct id) from schema2.compound) as count_new
)
select
'compound' as table_name,
count_old,
count_new,
count_old - count_new as diff
from counts;
I think you could do something like this:
SELECT 'compound' AS table_name, count_old, count_new, (count_old - count_new) AS diff FROM (
SELECT(
(SELECT count(*) FROM (SELECT DISTINCT id FROM schema1.compound)) AS count_old,
(SELECT count(*) FROM (SELECT DISTINCT id FROM schema2.compound)) AS count_new
)
It was probably answered already, but it is a subquery/nested query.
You can directly compute the COUNT on distinct values if you use the DISTINCT keyword inside your aggregation function. Then you can join the queries extracting your two needed values, and use them inside your query to get the output table.
WITH cte AS (
SELECT new.cnt AS count_new,
old.cnt AS count_old
FROM (SELECT COUNT(DISTINCT id) AS cnt FROM schema1.compound) AS old
INNER JOIN (SELECT COUNT(DISTINCT id) AS cnt FROM schema2.compound) AS new
ON 1 = 1
)
SELECT 'compound' AS table_name,
count_new,
count_old,
count_new = count_old AS diff
FROM cte
How do I get the sum of all return rows with group by clause in DB2?
For example:
Desc Ctr
---- ---
Bowl 30
Plate 21
Spoon 6
Sum 57
SELECT COUNT (name) as Desc, Count(*) OVER ALL
GROUP BY name
Above query return error from DB2. What is the proper SQL statement to return SUM of all rows?
Thanks,
Brandon.
Try this query,
select name, count(*) from table group by name
What is your platform of Db2?
If you want just the total count of rows, then
select count(*)
from mytable
If you want the subtotals by name plus the total, SQL didn't originally support that. You had to union the two results.
select name, count(*) as cnt
from mytable
group by name
UNION ALL
select '', count(*)
from mytable
However more modern versions have added ROLLUP (and CUBE) functionality...
select name, count(*) as cnt
from mytable
group by name with rollup
Edit
To put a value for name, you could simply use COALESCE() assuming name won't ever be null except in the total row.
select coalesce(name,'-Total-') as name, count(*) as cnt
from mytable
group by name with rollup
The more correct method is to use the GROUPING() function
either return just the flag
select name, count(*) as cnt, grouping(name) as IS_TOTAL
from mytable
group by name with rollup
or use it to set the text
select case grouping(name)
when 1 then '-Total-'
else name
end as name
, count(*) as cnt
from mytable
group by name with rollup
Inculde total
To include the total on each line, you could do something like so...
with tot as (select count(*) as cnt from mytable)
select name
, count(*) as name_cnt
, tot.cnt as total_cnt
from mytable
cross join tot
group by name
Note that this will read mytable twice, once for the total and again for the detail rows. But it's real obvious what you're doing.
Another option would be something like so
with allrows as (
select name, count(*) as cnt, grouping(name) as IS_TOTAL
from mytable
group by name with rollup
)
select dtl.name, dtl.cnt, tot.cnt
from allrows dtl
join allrows tot
on tot.is_total = 1
where
dtl.is_total = 0
Wonder what would happen if i select both * and an aggregate together.
Will it be just one row or multiple rows?
example:
select *, count(*) from employee
I have a field called "Users", and I want to run SUM() on that field that returns the sum of all DISTINCT records. I thought that this would work:
SELECT SUM(DISTINCT table_name.users)
FROM table_name
But it's not selecting DISTINCT records, it's just running as if I had run SUM(table_name.users).
What would I have to do to add only the distinct records from this field?
Use count()
SELECT count(DISTINCT table_name.users)
FROM table_name
SQLFiddle demo
This code seems to indicate sum(distinct ) and sum() return different values.
with t as (
select 1 as a
union all
select '1'
union all
select '2'
union all
select '4'
)
select sum(distinct a) as DistinctSum, sum(a) as allSum, count(distinct a) as distinctCount, count(a) as allCount from t
Do you actually have non-distinct values?
select count(1), users
from table_name
group by users
having count(1) > 1
If not, the sums will be identical.
You can see for yourself that distinct works with the following example. Here I create a subquery with duplicate values, then I do a sum distinct on those values.
select DistinctSum=sum(distinct x), RegularSum=Sum(x)
from
(
select x=1
union All
select 1
union All
select 2
union All
select 2
) x
You can see that the distinct sum column returns 3 and the regular sum returns 6 in this example.
You can use a sub-query:
select sum(users)
from (select distinct users from table_name);
SUM(DISTINCTROW table_name.something)
It worked for me (innodb).
Description - "DISTINCTROW omits data based on entire duplicate records, not just duplicate fields." http://office.microsoft.com/en-001/access-help/all-distinct-distinctrow-top-predicates-HA001231351.aspx
;WITH cte
as
(
SELECT table_name.users , rn = ROW_NUMBER() OVER (PARTITION BY users ORDER BY users)
FROM table_name
)
SELECT SUM(users)
FROM cte
WHERE rn = 1
SQL Fiddle
Try here yourself
TEST
DECLARE #table_name Table (Users INT );
INSERT INTO #table_name Values (1),(1),(1),(3),(3),(5),(5);
;WITH cte
as
(
SELECT users , rn = ROW_NUMBER() OVER (PARTITION BY users ORDER BY users)
FROM #table_name
)
SELECT SUM(users) DisSum
FROM cte
WHERE rn = 1
Result
DisSum
9
If circumstances make it difficult to weave a "distinct" into the sum clause, it will usually be possible to add an extra "where" clause to the entire query - something like:
select sum(t.ColToSum)
from SomeTable t
where (select count(*) from SomeTable t1 where t1.ColToSum = t.ColToSum and t1.ID < t.ID) = 0
May be a duplicate to
Trying to sum distinct values SQL
As per Declan_K's answer:
Get the distinct list first...
SELECT SUM(SQ.COST)
FROM
(SELECT DISTINCT [Tracking #] as TRACK,[Ship Cost] as COST FROM YourTable) SQ
I made two queries that I thought should have the same result:
SELECT COUNT(*) FROM (
SELECT DISTINCT ON (id1) id1, value
FROM (
SELECT table1.id1, table2.value
FROM table1
JOIN table2 ON table1.id1=table2.id
WHERE table2.value = '1')
AS result1 ORDER BY id1)
AS result2;
SELECT COUNT(*) FROM (
SELECT DISTINCT ON (id1) id1, value
FROM (
SELECT table1.id1, table2.value
FROM table1
JOIN table2 ON table1.id1=table2.id
)
AS result1 ORDER BY id1)
AS result2
WHERE value = '1';
The only difference being that one had the WHERE clause inside SELECT DISTINCT ON, and the other outside that, but inside SELECT COUNT. But the results were not the same. I don't understand why the position of the WHERE clause should make a difference in this case. Can anyone explain? Or is there a better way to phrase this question?
here's a good way to look at this:
SELECT DISTINCT ON (id) id, value
FROM (select 1 as id, 1 as value
union
select 1 as id, 2 as value) a;
SELECT DISTINCT ON (id) id, value
FROM (select 1 as id, 1 as value
union
select 1 as id, 2 as value) a
WHERE value = 2;
The problem has to do with the unique conditions and what is visible where. It is behavior by design.