I've built a query for a summary table of information, and it's almost there, with one small bug. The confirmed_class_count variable comes back too high if there's multiple users on a class, leading me to believe that the number isn't distinct
Here's my current code:
SELECT "staffs".*,
count(distinct subclasses) as class_count,
sum(case when users.confirmed_at is not null then 1 else 0 end) confirmed_class_count
FROM
staffs
INNER JOIN classes as subclasses on staffs.staff_id = ANY(subclasses.staff)
INNER JOIN "classes_users" ON "classes_users"."class_id" = "subclasses"."id"
INNER JOIN "users" ON "users"."id" = "classes_users"."user_id"
INNER JOIN class_types ON class_types.code = subclasses.class_type_code
WHERE
(subclasses.closed_date is NULL OR subclasses.closed_date > '2019-09-06')
GROUP BY
staffs.id ORDER BY "staffs"."full_name" ASC
I want to replace the sum with something like (select distinct count(*) from subcases where users.confirmed_at is not null) as confirmed_case_count but I get relation "subclasses" does not exist.
How do I get what I'm intending here?
You can use count distinct with conditional aggregation. Replace
sum(class when users.confirmed_at is not null then 1 else 0 end) confirmed_class_count
^ looks like a typo, this should be case not class
with
count(distinct case when users.confirmed_at is not null then classes_users.class_id end) confirmed_class_count
Related
I have 2 tables; the first one ORG contains the following columns:
ORG_REF, ARB_REF, NAME, LEVEL, START_DATE
and the second one WORK contains these columns:
ARB_REF, WORK_STREET - WORK_NUM, WORK_ZIP
I want to do the following: write a select query that search in work and see if the WORK_STREET, WORK_ZIP are duplicate together, then you should look at WORK_NUM. If it is the same then output value ' ok ', but if WORK_NUM is not the same, output 'not ok'
I wrote this SQL query:
select
A.ARB_REF, A.WORK_STREET, A.WORK_NUM, A.WORK_ZIP
case when B.B = 1 then 'OK' else 'not ok' end
from
work A
join
(select
WORK_STREET, WORK_ZIP count(distinct , A.WORK_NUM) B
from
WORK
group by
WORK_STREET, WORK_ZIP) B on B.WORK_STREET = A.WORK_STREET
and B.WORK_ZIP = A.WORK_ZIP
Now I want to join the table ORG with this result I want to check if every address belong to org if it belong I should create a new column result and set it to yes in it (RESULT) AND show the "name" column otherwise set no in 'RESULT'.
Can anyone help me please?
While you can accomplish your result by adding a left outer join to the query you've already started, it might be easiest to just use count() over....
with org_data as (
-- do the inner join before the left join later
select * from org1 o1 inner join org2 o2 on o2.orgid = o1.orgid
)
select
*,
count(*) over (partition by WORK_STREET, WORKZIP) as cnt,
case when o.ARB_REF is not null then 'Yes' else 'No' end as result
from
WORK w left outer join org_data o on o.ARB_REF = w.ARB_REF
I am working on Postgres and I have two tables vehicles and vehicles_flag. There are no relations between the two tables and hence we can not join two tables to fetch the required data.
The table structure is below (vehicle_flag table may not contain all the id present in the vehicle table) :
[Table structure]
I am writing a function that will accept multiple input parameters. I have to select vehicle id from the vehicle_flag table only if the flag value is true: otherwise, I have to ignore the vehicel_flag table. My aim is to achieve something like this, but turns out the case statement expects scaler output:
select count(id) from vehicles
where
vehicles.id in (case
when #hasbluetooth =1 then (select distinct id from vehicle_flags where flag='bluetooth' and value = '1')
else
(select distinct id from vehicles)
end)
and
vehicles.id in (case
when #hasac =1 then (select distinct id from vehicle_flags where flag='ac' and value = '1')
else
(select distinct id from vehicles)
end)
Kindly suggest any solution to achieve this.
I suspect you want:
select v.*
from vehicle v
left join vehicle_flags vf on vf.id = v.id
group by v.id
having
(#hasbluetooth = 0 or bool_or(vf.flag = 'bluetooth' and vf.value = 1)
and (#hasac = 0 or bool_or(vf.flag = 'ac' and vf.value = 1)
I have a simple table with some data. I would like to write query, which returns "cas number" of objects, which have more "sent" rows, than "rent" rows. My query is attached below:
select
c1.cas
from
casdat c1
join
casdat c2
on
c1.cas=c2.cas
and c1.type='sent'
and c2.type='rent'
group by
c1.cas
having
count(distinct c1.data) > count(distinct c2.data);
The problem is, my query does not process a case, when some specific "cas" has few "sent" rows and 0 "rent" ones. How to include such a case for my query? I would like to keep the JOIN clause. I know i could write a subquery and count it like that:
select c1.cas,count(distinct c1.data) from casdat c1
where c1.type='sent'
group by c1.cas
having count(distinct c1.data)>
(select count(distinct c2.data) from casdat c2 where c2.type='rent' and
c2.cas=c1.cas);
I would like that my query works like the second one attached here, but i need to use join clause. How to write such a query?
Use aggregation with a having clause:
select c.cas
from casdat c
group by c.ca
having sum(case when c.type = 'sent' then 1 else 0 end) > sum(case when c.type = 'rent' then 1 else 0 end);
I have used a left join on two of my tables. Now I want to use case to identify the records from my left table who don't have a match in the right table. Such records exist and have a null value in the 'id_zeus' column of my join, however when I execute the case, it is as these fields don't exist. Where am I going wrong ? I get "Present" in all my column Disturbance. I am using Oracle SQL developer.
SELECT
CASE DP.ID_PRB
WHEN NULL
THEN 'Absence'
ELSE 'Present' END as Disturbance,
FROM
FIRE.WSITE WI
LEFT JOIN
(SELECT DISTINCT
DPL.ID_PERT as ID_PRB
FROM FIRE.DEPPLAN DPL
GROUP BY DPL.ID_PERT
) DPL
ON WI.ID_PERT = DP.ID_PERT
What is const? You don't seem to need it. The SELECT DISTINCT and GROUP BY are redundant, so use only one of them. And your alias on the subquery is incorrect.
But your problem is the comparison to NULL. It doesn't even match when doing a comparison as you are doing in CASE. You need to use IS NULL:
SELECT (CASE WHEN DP.ID_PRB IS NULL THEN 'Absence' ELSE 'Present'
END) as Disturbance,
FROM FIRE.WSITE WI LEFT JOIN
(SELECT DISTINCT DPL.ID_PERT as ID_PRB
FROM FIRE.OSI_DEVIATION_PLANS DP
) DP
ON WI.ID_PERT = DP.ID_PERT;
This query would commonly be written as:
SELECT (CASE WHEN NOT EXISTS (SELECT 1
FROM FIRE.OSI_DEVIATION_PLANS DP
WHERE WI.ID_PERT = DP.ID_PERT
)
THEN 'Absence' ELSE 'Present'
END) as Disturbance,
FROM FIRE.WSITE WI ;
This offers more opportunities for optimization.
I have these three tables:
table_things: [id]
table_location: [id]
[location]
[quantity]
table_reservation: [id]
[quantity]
[location]
[list_id]
Example data:
table_things:
id
1
2
3
table_location
id location quantity
1 100 10
1 101 4
2 100 1
table_reservation
id quantity location list_id
1 2 100 500
1 1 100 0
2 1 100 0
They are connected by [id] being the same in all three tables and [location] being the same in table_loation and table_reservation.
[quantity] in table_location shows how many ([quantity]) things ([id]) are in a certain place ([location]).
[quantity] in table_reservation shows how many ([quantity]) things ([id]) are reserved in a certain place ([location]).
There can be 0 or many rows in table_reservation that correspond to table_location.id = table_reservation_id, so I probably need to use an outer join for that.
I want to create a query that answers the question: How many things ([id]) are in this specific place (WHERE table_location=123), how many of of those things are reserved (table_reservation.[quantity]) and how many of those that are reserved are on a table_reservation.list_id where table_reservation.list_id > 0.
I can't get the aggregate functions right to where the answer contains only the number of lines that are in table_location with the given WHERE clause and at the same time I get the correct number of table_reservation.quantity.
If I do this I get the correct number of lines in the answer:
SELECT table_things.[id],
table_location.[quantity],
SUM(table_reservation.[quantity]
FROM table_location
INNER JOIN table_things ON table_location.[id] = table_things.[id]
RIGHT OUTER JOIN table_reservation ON table_things.location = table_reservation.location
WHERE table_location.location = 100
GROUP BY table_things.[id], table_location[quantity]
But the problem with that query is that I (of course) get an incorrect value for SUM(table_reservation.[quantity]) since it sums up all the corresponding rows in table_reservation and posts the same value on each of the rows in the result.
The second part is trying to get the correct value for the number of table_reservation.[quantity] whose list_id > 0. I tried something like this for that, in the SELECT list:
(SELECT SUM(CASE WHEN table_reservation.list_id > 0 THEN table_reservation.[quantity] ELSE 0 END)) AS test
But that doesn't even parse... I'm just showing it to show my thinking.
Probably an easy SQL problem, but it's been too long since I was doing these kinds of complicated queries.
For your first two questions:
How many things ([id]) are in this specific place (WHERE table_location=123), how many of of those things are reserved (table_reservation.[quantity])
I think you simply need a LEFT OUTER JOIN instead of RIGHT, and an additional join predicate for table_reservation
SELECT l.id,
l.quantity,
Reserved = SUM(ISNULL(r.quantity, 0))
FROM table_location AS l
INNER JOIN table_things AS t
ON t.id = l.ID
LEFT JOIN table_reservation r
ON r.id = t.id
AND r.location = l.location
WHERE l.location = 100
GROUP BY l.id, l.quantity;
N.B I have added ISNULL so that when nothing is reserved you get a result of 0 rather than NULL. You also don't actually need to reference table_things at all, but I am guessing this is a simplified example and you may need other fields from there so have left it in. I have also used aliases to make the query (in my opinion) easier to read.
For your 3rd question:
and how many of those that are reserved are on a table_reservation.list_id where table_reservation.list_id > 0.
Then you can use a conditional aggregate (CASE expression inside your SUM):
SELECT l.id,
l.quantity,
Reserved = SUM(r.quantity),
ReservedWithListOver0 = SUM(CASE WHEN r.list_id > 0 THEN r.[quantity] ELSE 0 END)
FROM table_location AS l
INNER JOIN table_things AS t
ON t.id = l.ID
LEFT JOIN table_reservation r
ON r.id = t.id
AND r.location = l.location
WHERE l.location = 100
GROUP BY l.id, l.quantity;
As a couple of side notes, unless you are doing it for the right reasons (so that different tables are queried depending on who is executing the query), then it is a good idea to always use the schema prefix, i.e. dbo.table_reservation rather than just table_reservation. It is also quite antiquated to prefix your object names with the object type (i.e. dbo.table_things rather than just dbo.things). It is somewhat subject, but this page gives a good example of why it might not be the best idea.
You can use a query like the following:
SELECT tt.[id],
tl.[quantity],
tr.[total_quantity],
tr.[partial_quantity]
FROM table_location AS tl
INNER JOIN table_things AS tt ON tl.[id] = tt.[id]
LEFT JOIN (
SELECT id, location,
SUM(quantity) AS total_quantity,
SUM(CASE WHEN list_id > 0 THEN quantity ELSE 0 END) AS partial_quantity
FROM table_reservation
GROUP BY id, location
) AS tr ON tl.id = tr.id AND tl.location = tr.location
WHERE tl.location = 100
The trick here is to do a LEFT JOIN to an already aggregated version of table table_reservation, so that you get one row per id, location. The derived table uses conditional aggregation to calculate field partial_quantity that contains the quantity where list_id > 0.
Output:
id quantity total_quantity partial_quantity
-----------------------------------------------
1 10 3 2
2 1 1 0
This was a classic case of sitting with a problem for a few hours and getting nowhere and then when you post to stackoverflow, you suddenly come up with the answer. Here's the query that gets me what I want:
SELECT table_things.[id],
table_location.[quantity],
SUM(table_reservation.[quantity],
(SELECT SUM(CASE WHEN table_reservation.list_id > 0 THEN ISNULL(table_reservation.[quantity], 0) ELSE 0 END)) AS test
FROM table_location
INNER JOIN table_things ON table_location.[id] = table_things.[id]
RIGHT OUTER JOIN table_reservation ON table_things.location = table_reservation.location AND table_things.[id] = table_reservation.[id]
WHERE table_location.location = 100
GROUP BY table_things.[id], table_location[quantity]
Edit: After having read GarethD's reply below, I did the changes he suggested (to my real code, not to the query above) which makes the (real) query correct.