Get separate count for each condition within group - sql

I am trying to get a view of table information from and Oracle 10g table that lists the counts of specific values of a column in their own columns with each row being the group value.
for example:
The first select is :
SELECT processed_by, count(priority) as P2
FROM agreement_activity
WHERE priority = '2'
GROUP BY processed_by
Which outputs:
PROCESSED_BY P2
------------------------------ ----------
Alicia 2
Christine 2
The second select is:
SELECT processed_by, count(priority) as P1
FROM agreement_activity
WHERE priority = '1'
GROUP BY processed_by
Which outputs:
PROCESSED_BY P1
------------------------------ ----------
Bonita 2
Alicia 6
Christine 2
What I am looking for is to output those values as the following:
PROCESSED_BY P1 P2
------------------------------ ---------- ----------
Bonita 2
Alicia 6 2
Christine 2 2
Is that possible?

You can use sum with the case expression to get conditional count:
select processed_by
, sum(case when priority = 1 then 1 else 0 end) as P1
, sum(case when priority = 2 then 1 else 0 end) as P2
from agreement_activity
group by processed_by
P.S. If you don't care that P1 or P2 maybe null instead of 0 you can omit else in both expressions.

this is how I implement the sql. I'm using firebird code but I think you can convert the code into your sql
SELECT
a.equipmentid,
a.name equipname,
w1.countwarranty1 ,
w2.countwarranty2
FROM TBL_EQUIPMENTMST a
inner JOIN
(select c.equipmentid, count(c.WARRANTYID) countwarranty1 from tbl_equipwarranty c where c.serviceproduct='1' group by c.equipmentid) w1
ON w1.equipmentid = a.equipmentid
inner JOIN
(select d.equipmentid, count(d.WARRANTYID) countwarranty2 from tbl_equipwarranty d where d.serviceproduct='2' group by d.equipmentid) w2
ON w2.equipmentid = a.equipmentid
inner JOIN
(select e.equipmentid, count(e.equiplocationid) countlocation from tbl_equiplocation e group by e.equipmentid) w3
ON w3.equipmentid = a.equipmentid
this is the output
My warranty table has only 2 warranty for equipment each that's why its only showing 2.
you can also inner join to the same table with different count.
as you can see my warranty has multiple warranty where serviceproduct is different on each table
if I edit your code it will be like this
SELECT a.processed_by, b.priority as p2, c.priority as p1
FROM agreement_activity a
inner join
(
SELECT w1.processed_by, count(w1.priority) as P2 FROM agreement_activity w1
WHERE w1.priority = '2' GROUP BY w1.processed_by
) b
on a.processed_by = b.processed_by
inner join
(
SELECT w2.processed_by, count(w2.priority) as P2 FROM w2.agreement_activity
WHERE w2.priority = '1' GROUP BY w2.processed_by
) c
on a.processed_by = c.processed_by
test it

Related

SQL query doesnt return expected values

I have 3 tables. 1st table stores coil information, 2nd table store coil information in transport and 3rd stores reserved coils.
coils
ID
SERIAL
COLOR
MATERIAL
STATUS
1
12345
5
1
2
2
12346
4
1
3
3
12347
3
1
2
coils_in_transport
ID
SERIAL
COLOR
MATERIAL
STATUS
1
f34S5
5
1
2
2
A23GG6
4
1
3
3
ff2S147
3
1
2
reserved_coils
ID
NUMBER
QUANTITY
START
END
1
12345
25
2022-05-01
2023-05-01
3
12347
252
2022-01-01
2023-05-01
4
A23GG6
33
2022-04-01
2023-05-01
5
ff2S147
35
2022-08-01
2023-05-01
I need to write query that will get all reserved coils (reserved_coils) that has status 2 and for each coil I need to join tables for materials and colors
material
ID
NAME
1
color
ID
NAME
I wrote query but it doesn't show coils in transport that are reserved, here is what I tried
SELECT a.QUANTITY, a.START, a.END, b.name, m.name
FROM reserved_coils a
LEFT JOIN coils b ON a.number = b.serial
LEFT JOIN coils_in_transport c ON a.number = c.serial
LEFT JOIN material m ON b.material = m.id
LEFT JOIN material b ON b.material = b.id
where b.status = 2 and c.status = 2
To get all coils and colis_in_transport you need to use UNION for SELECT statements for both tables, each filtered by status value, which should be equal to 2. Then you need to do a JOIN between reserved_coils and the result of UNION to filter out reserved_coils rows.
Your query would be like this
SELECT
r.quantity,
r.start,
r.[end],
c.serial,
material.name AS material,
color.name AS color
FROM reserved_coils r
JOIN (
SELECT * FROM coils WHERE status = 2
UNION
SELECT * FROM coils_in_transport WHERE status = 2
) c ON r.number = c.serial
LEFT JOIN material ON material.id = c.material
LEFT JOIN color ON color.id = c.color
Demo
If you want left join twice on same table, this might help
SELECT a.QUANTITY, a.START, a.[END], isnull(b.serial,c.serial) serial,isnull(c1.name,c2.name) color, isnull(m.name,n.name) material
FROM reserved_coils a
LEFT JOIN coils b ON a.number = b.serial
LEFT JOIN coils_in_transport c ON a.number = c.serial
LEFT JOIN material m ON b.material = m.id
LEFT JOIN material n ON c.material = n.id
LEFT JOIN color c1 on b.color=c1.id
LEFT JOIN color c2 on c.color=c2.id
where isnull(b.status,c.status) = 2
DB<>Fiddle

Query to show one column multiplied

I have the following 3 tables;
Table_Names:
user_id Name
------------------
1 Mark
2 Tom
3 Ana
Table_Language:
language_id Language
-----------------------
1 English
2 German
Table_Name_Lang
id user_id language_id
---------------------------
1 1 1
2 1 2
3 2 1
4 3 2
How can I create a query to show the expected results like those below?
Name Expr_1_Eng Expr_1_Ger
---------------------------------
Mark English German
Tom English
Ana German
Thanks Tok
I would do:
select n.name,
max(case when l.language = 'English' then l.language end) as has_English,
max(case when l.language = 'German' then l.language end) as has_German
from names n join
name_lang nl
on nl.user_id = n.user_id join
lang l
on nl.language_id = l.language_id
group by n.name
You can try to use JOIN with condition aggregate function
SELECT Name,
MAX(CASE WHEN tnl.language_id = 1 then tl.Language end),
MAX(CASE WHEN tnl.language_id = 2 then tl.Language end)
FROM
Table_Name_Lang tnl
JOIN Table_Names tn on tnl.language_id = tn.language_id
JOIN Table_Language tl on tl.user_id = tnl.user_id
GROUP BY Name
I think you should use pivot:
select n.name,[0] as language_one,[1] as language_two,[2],[3] from
(select n.name,tl.language
tablename n
left join Table_Name_Lang tnl on n.userid=tnl.userid
left join table_language tl on tl.id=tnl.id
group by n.name,tl.language
)T
pivot
(
language
for name in [0],[1],[2],[3]
)AS PivotTable;

Use Count function inside conditional part of Case Expression

I have two tables with the following sample records in oracle database
1. staffs
inst_name name sid
ABC John 1
PQR Sam 2
ABC Tom 3
ABC Amit 4
PQR Jack 5
2. staffaccounts
sid account_no
1 4587
1 4588
2 4589
3 4581
3 4582
5 4583
5 4585
4 4586
Where I want the result like
inst_name account_type total
PQR SINGLE 1
ABC SINGLE 1
PQR DOUBLE 1
ABC DOUBLE 2
This can be achieved by a outer query, but I want to write a query where there is no outer query. Want to accomplish it in one single query.
SELECT
A .inst_name,
(
CASE COUNT (b.ac_no)
WHEN 1 THEN
'Single'
WHEN 2 THEN
'Double'
END
) account_type,
COUNT (A . NAME)
FROM
staffs A,
staffaccounts b
WHERE
A . s_id = b.s_id
GROUP BY
A .inst_name
The above query gives error ORA-00907: missing right parenthesis. Can it be done in single query or is outer query the only way out.
Oracle Version is 10g
May be something like this would work.
SELECT
A.inst_name,
CASE COUNT (b.account_no)
WHEN 1 THEN
'Single'
WHEN 2 THEN
'Double'
END account_type,
COUNT (A.name)
FROM
staffs A JOIN
staffaccounts b
ON
A.SID = b.sid
GROUP BY
A.inst_name , a.sid
ORDER BY 3;
You are grouping by inst_name, but this is not what you actually want, because you don't want a result row per inst_name, but per inst_name and account_type.
select
s.inst_name,
sa.account_type,
count(*) as total
from staffs s
join
(
select
sid,
case when count(*) = 1 then 'SINGLE' else 'DOUBLE' end as account_type
from staffaccounts
group by sid
having count(*) <= 2
) sa on sa.sid = s.sid
group by sa.account_type, s.inst_name
order by sa.account_type, s.inst_name;
You should learn how to properly use JOIN syntax. I prefer the explicit comparison syntax for CASE.
This may be what you want:
SELECT s.inst_name,
(CASE WHEN COUNT(sa.ac_no) = 1 THEN 'Single'
WHEN COUNT(sa.ac_no) = 2 THEN 'Double'
END) as account_type,
COUNT(*)
FROM staffs s JOIN
staffaccounts sa
ON s.SID = sa.sid
GROUP BY s.inst_name;
EDIT:
Now I see what you want:
SELECT s.inst_name,
(CASE WHEN cnt = 1 THEN 'Single'
WHEN cnt = 2 THEN 'Double'
END) as account_type,
COUNT(*)
FROM (SELECT s.*, COUNT(*) as cnt
FROM staffs s JOIN
staffaccounts sa
ON s.SID = sa.sid
GROUP BY s.id
) s
GROUP BY s.inst_name,
(CASE WHEN cnt = 1 THEN 'Single'
WHEN cnt = 2 THEN 'Double'
END);
I got only the way by using subquery but is in the easy way (more easier and readable) to achieve your requirement
SELECT inst_name, account_type, count(total) as total
FROM (
SELECT
a.inst_name,
CASE
WHEN COUNT (b.account_no) = 1 THEN 'Single'
WHEN COUNT (b.account_no) = 2 THEN 'Double'
END AS account_type,
COUNT (a.name) AS total
FROM staffs a
INNER JOIN staffaccounts b ON A . SID = b.sid
GROUP BY a.inst_name, a.sid) t GROUP BY inst_name, account_type
OUTPUT:
inst_name account_type total
ABC Double 2
PQR Double 1
ABC Single 1
PQR Single 1

"If one-to-many table has value" as column in SELECT

I have one table with cars, and another table with fuel types. A third table tracks which cars can use which fuel types. I need to select all data for all cars, including which fuel types they can use:
Car table has Car_ID, Car_Name, etc
Fuel table has Fuel_ID, Fuel_Name
Car_Fuel table has Car_ID, Fuel_ID (one car can have multiple Fuel options)
What I want to return:
SELECT
*
, Can_Use_Gas
, Can_Use_Diesel
, Can_Use_Electric
FROM Car
The Can_Use columns are a BIT value, indicating if the car has a matching Fuel entry in the Car_Fuel table.
I can do this with multiple SELECT statements, but this looks painfully messy (and possibly very inefficient?). I'm hoping there's a better way:
SELECT
c.*
, (SELECT COUNT(*) FROM Car_Fuel f WHERE f.Car_ID = c.Car_ID AND f.Fuel_ID = 1) AS Can_Use_Gas
, (SELECT COUNT(*) FROM Car_Fuel f WHERE f.Car_ID = c.Car_ID AND f.Fuel_ID = 2) AS Can_Use_Diesel
, (SELECT COUNT(*) FROM Car_Fuel f WHERE f.Car_ID = c.Car_ID AND f.Fuel_ID = 3) AS Can_Use_Electric
FROM Car c
Presumably you have no duplicates in Car_fuel, so you don't need aggregation. Hence you can do:
SELECT c.*,
ISNULL((SELECT TOP 1 1 FROM Car_Fuel f WHERE f.Car_ID = c.Car_ID AND f.Fuel_ID = 1), 0) AS Can_Use_Gas
ISNULL((SELECT TOP 1 1 FROM Car_Fuel f WHERE f.Car_ID = c.Car_ID AND f.Fuel_ID = 2), 0) AS Can_Use_Diesel
ISNULL((SELECT TOP 1 1 FROM Car_Fuel f WHERE f.Car_ID = c.Car_ID AND f.Fuel_ID = 3), 0) AS Can_Use_Electric
FROM Car c;
This is one case where ISNULL() has a performance advantage over COALESCE(), because COALESCE() evaluates the first argument twice.
Although not a perfect solution, you could use the pivot clause:
select *
from ( select car_name, fuel_name
from Car
inner join Car_Fuel on Car.car_id = Car_Fuel.car_id
inner join Fuel on Car_Fuel.fuel_id = Fuel.fuel_id
) as data
pivot (
count(fuel_name)
for fuel_name in (Gas, Diesel, Electric)
) as pivot_table;
See this fiddle, which outputs a table like this:
| car_name | Gas | Diesel | Electric |
|----------|-----|--------|----------|
| Jaguar | 0 | 1 | 0 |
| Mercedes | 0 | 1 | 1 |
| Volvo | 1 | 0 | 1 |
The SQL statement still has the hard-coded list in the for clause of the pivot part, but when the number of fuel types increases, this might be easier to manage and have better performance.
Generating the SQL dynamically
If you use an application server, you could first execute this query:
SELECT stuff( ( SELECT ',' + fuel_name
FROM Fuel FOR XML PATH('')
), 1, 1, '') columns
This will return the list of columns as one comma-separated value, for example:
Gas,Diesel,Electric
You would grab that result and inject it in the first query in the FOR clause.
I would suspect using counts would be inefficient as there would be a large number of sub queries running to total all the counts.
Below is an alternative using self joins. It's not as short as your example but may be easier to maintain and read and should be more efficient.
select car.car_id, car.car_name,
-- Select fuel variables
CASE WHEN lpg.fuel_id IS NULL THEN 0 ELSE 1 END AS LPG,
CASE WHEN unleaded.fuel_id IS NULL THEN 0 ELSE 1 END AS Unleaded,
CASE WHEN electric.fuel_id IS NULL THEN 0 ELSE 1 END AS Electric,
CASE WHEN diesel.fuel_id IS NULL THEN 0 ELSE 1 END AS Diesel
FROM car
-- Self Join fuel records
LEFT join car_fuel as lpg on car.car_id = lpg.car_id and lpg.fuel_id = 1
LEFT join car_fuel as unleaded on car.car_id = unleaded.car_id and unleaded.fuel_id = 2
LEFT join car_fuel as electric on car.car_id = electric.car_id and electric.fuel_id = 3
LEFT join car_fuel as diesel on car.car_id = diesel.car_id and diesel.fuel_id = 4
The self join will return a NULL if the car doesn't use that fuel type. The CASE returns 1 if the join found a record for that car/fuel and 0 if it didn't.
I hope this help.
You could use conditional aggregation.
Do an outer join to the Car_Fuel table, and do a GROUP BY Car_ID to collapse the rows.
For each row from Car_Fuel, return a 1 if the Fuel_ID matches the one you are checking for, otherwise return a 0. And use a MAX() aggregate to filter the rows, finding out if any of them returned a 1.
For example:
SELECT c.Car_ID
, c.Car_Name
, MAX(CASE WHEN f.Fuel_ID=1 THEN 1 ELSE 0 END) AS Can_Use_Gas
, MAX(CASE WHEN f.Fuel_ID=2 THEN 1 ELSE 0 END) AS Can_Use_Diesel
, MAX(CASE WHEN f.Fuel_ID=3 THEN 1 ELSE 0 END) AS Can_Use_Electric
FROM Car c
LEFT
JOIN Car_Fuel f
ON f.Car_ID = c.Car_ID
GROUP
BY c.Car_ID
, c.Car_Name
With SQL Server, you'd need to repeat every non-aggregate expression in the SELECT list in the GROUP BY clause. If you add more columns from the Car table to SELECT list, you'll have to copy those down to the GROUP BY.
If that's too painful, you could do the aggregation in an inline view instead, and then do the JOIN. To make sure a NULL doesn't get returned, you can replace a NULL value with a 0, in the outer query:
For example:
SELECT c.Car_ID
, c.Car_Name
, ISNULL(u.Can_Use_Gas,0) AS Can_Use_Gas
, ISNULL(u.Can_Use_Diesel,0) AS Can_Use_Diesel
, ISNULL(u.Can_Use_Electric,0) AS Can_Use_Electric
FROM Car c
LEFT
JOIN ( SELECT f.Car_ID
, MAX(CASE WHEN f.Fuel_ID=1 THEN 1 ELSE 0 END) AS Can_Use_Gas
, MAX(CASE WHEN f.Fuel_ID=2 THEN 1 ELSE 0 END) AS Can_Use_Diesel
, MAX(CASE WHEN f.Fuel_ID=3 THEN 1 ELSE 0 END) AS Can_Use_Electric
FROM Car_Fuel f
GROUP BY f.Car_ID
) u
ON u.Car_ID = c.Car_ID

Join a table with one table if condition1 is true and with another table if condition1 is false?

I have the following tables :
User_Group
id group_id group_type
------------------------
1 100 A
1 100 B
2 101 B
2 102 A
Group_A
id name
---------
100 A
101 B
102 C
Group_B
id name
---------
100 D
101 E
102 F
I want the group names of all users (using array.agg()). We have to get the group name from group A if the user's group type = A and from group B if the user's group type = B. The result should be :
userid groups
--------------
1 A,D
2 E,C
I have created a fiddle for this, and given a solution using union of 2 separate queries. Can it be done without the union, something in which I can decide on which table to pick the group name from with a single join of user_groups, group_A and group_B ?
select ug.id, array_agg(
case ug.group_type
when 'A' then g_a.name
when 'B' then g_b.name
else 'N/A'
end)
from user_groups ug
left outer join group_A g_a on ug.group_id = g_a.id
left outer join group_B g_b on ug.group_id = g_b.id
group by ug.id
SQL Fiddle Example
You can do this without union using left joins (I'd advise using explicit joins anyway since implicit joins are 20 years out of date Aaron Bertrand has written a good blog as to why). The Group_Type can become a join condition meaning the table is only joined when the right group type is found:
SELECT ug.ID, ARRAY_AGG(COALESCE(a.Name, b.Name))
FROM User_Groups ug
LEFT JOIN group_A a
ON a.ID = ug.group_ID
AND ug.Group_Type = 'A'
LEFT JOIN group_B b
ON b.ID = ug.group_ID
AND ug.Group_Type = 'B'
WHERE COALESCE(a.ID, b.ID) IS NOT NULL -- ENSURE AT LEAST ONE GROUP IS MATCHED
GROUP BY ug.ID;
However I would be inclined to use a UNION Still, but move it as follows:
SELECT ug.ID, ARRAY_AGG(Name)
FROM User_Groups ug
INNER JOIN
( SELECT 'A' AS GroupType, ID, Name
FROM Group_A
UNION ALL
SELECT 'B' AS GroupType, ID, Name
FROM Group_B
) G
ON g.GroupType = ug.Group_Type
AND g.ID = ug.Group_ID
GROUP BY ug.ID;
Your Fiddle with my queries added