This question already exists:
Use left join and inner join with more than 2 tables
Closed 4 months ago.
Here you can see I have three tables
Student table
Stud_id Name Br_id Email City_id
1001 Ankit 101 ankit#bmail.com 1
1002 Pranav 105 pranav#bmail.com 2
1003 Raj 102 raj#bmail.com 2
1004 Shyam 112 shyam#bmail.com 4
1005 Duke 112 duke#bmail.com 2
1006 Jhon 102 jhon#bmail.com 3
1007 Aman 101 aman#bmail.com 4
1008 Pavan 111 pavan#bmail.com 13
1009 Virat 112 virat#bmail.com 12
Branch Table
Br_id Br_name HOD Contact
101 CSE SH Rao 22345
102 MECH AP Sharma 28210
103 EXTC VK Reddy 34152
104 CHEM SK Mehta 45612
105 IT VL Shelke 22521
106 AI KH Verma 12332
107 PROD PG Kakde 90876
Address Table
City_id City Pincode
1 Mumbai 400121
2 Pune 450011
3 Lucknow 553001
4 Delhi 443221
5 Kolkata 213445
6 Chennai 345432
7 Nagpur 323451
8 Sri Nagar 321321
I am using here three tables first one is a student table and the second one is a Branch table and the third one is an Address table
So I am writing a query like this here you can see below
select [Name], Br_name, City
from student
inner join Branch on student.Br_id = Branch.Br_id
left join [Address] on student.City_id = [Address].City_id
I have three tables I want to show here the student's name and branch name city name, but I want to show the student who has their branch only. I also want to show the student who has their city as well as show a student who does not have any city.
I wrote the query above but here I am not getting the result. Here student's name who does not have any city what's wrong here in my above join SQL query?
Here as you can see I am getting this result which I do not want to show
Name Br_name City
Ankit CSE Mumbai
Pranav IT Pune
Raj MECH Pune
Jhon MECH Lucknow
Aman CSE Delhi
Why can I not get the students who do not have a city and who have a city? What's wrong here in my join query what I am missing here?
Please let me know what's wrong in my above join query what should I do to get proper result? I have given three tables above
You can see that and why I am not able to get the result what I want to show what is the wrong in the above my join query please let me know
I hope someone will help me. Thank you so much.
I have the following tables
---SALARY_ITEMS---
PERSONID | EMPLOYMENT _REF | GROUP1 | CODE | FROM | END | QUANTI
000101 XYX 400 11101 2020-02-12 2020-02-12 12
000101 XYX 300 1100 2020-01-29 2020-02-29 1
000102 XYY 450 11111 2020-02-01 2020-02-12 19
000102 XYY 400 11101 2020-02-02 2020-02-12 82
000103 XYA 500 1100 2020-02-10 2020-02-12 11
000104 XYB 700 1100 2020-01-12 2020-02-12 24
---PERSON ---
PERSONID NAME
000101 Carolina
000102 Helen
000103 Jack
000104 Anna
---EMPLOYMENT---
PERSONID EMPLOYMENT _REF POSITION
000101 XYX doctor
000102 XYY nurse
000103 XYA nurse
000104 XYB Proffesor
----absent---
PERSONID CODE2 FROM END
000101 123 2020-03-01 2020-06-30
000102 120 2020-02-05 2020-02-13
000102 123 2020-03-01 2020-03-28
000103 115 2020-05-05 2020-06-30
000104 123 2020-02-01 2020-05-30
What I tried to do: get all employee that they are doctor and nurse and have certain group with certain code and works over 100 hours in a 2020 -Feb.
The following SQL query give me what i want But i want to add something to my query that is :
create a new column to see if the employee was absent in the same period 2020-feb with absent code 120 or 119 or both.
If he was I will get the 'CODE2' ELSE 'NOTHING'.
How can I do this in DB2?
This is the result I need to get:
PERSONID | NAME | POSITION | QUANTITY |ABSENT (this what i want to have)
000102 Helen NURSE 101 120
Query:
SELECT
S.PERSONID, P.NAME,E.POSTION , sum(S.QUANTITY) as QUANTITY
FROM
SALARY_ITEMS S
LEFT JOIN
PERSON P ON S.PERSONID = P.PERSONID
LEFT JOIN
EMPLOYMENT E ON E.EMPLOYMENT_REF = S.EMPLOYMENT _REF
WHERE
S.group1 IN ('400', '440', '450', '470', '640')
AND S.code IN ('11101', '11111', '11121', '11131', '11141')
AND S.from >= '2020-02-01'
AND S.end <= '2020-02-29'
AND E.POSTION IN ('nurse', 'doctor')
AND (SELECT SUM(S2.QUANTITY) AS QUANTITY2
FROM SALARY_ITEMS S2
WHERE S2.group1 IN ('400', '440', '450', '470', '640')
AND S2.code IN ('11101', '11111', '11121', '11131', '11141')
AND S2.from >= '2020-02-01'
AND S2.end <= '2020-02-29'
AND S.PERSONID = S2.PERSONID) >= '100'
GROUP BY
S.PERSONID, P.NAME, E.POSTION
I have 2 ds as below
ds1:
CustId Name Street1 City
=================================
1 Ron 1 Mn strt Hyd
2 Ashok westend av Delhi
3 Rajesh 5th Cross Mumbai
4 Venki 2nd Main NY
ds2:
Id CustName CustAddr1 City
=========================================
11 Ron 1 Mn Street Hyd
12 Ron eastend avn Patna
13 Rajesh 2nd Main Mumbai
14 Girish 100ft rd BLR
15 Dinesh 60ft Mum
16 Rajesh 1st Cross Mumbai
I am trying to find an exact match like ds1.Name --> ds2.CustName, ds1.city --> ds2.city
Output:
GrpID Rec_Id Count ds1.cond Rec_Id Count ds2.cond
======================================================================
1 1 1 Ron + Hyd 1001 1 Ron + Hyd
2 2 1 Rajesh + Mumbai 1002 2 Rajesh + Mumbai
How to write (SPARK) SQL query for it?
I tried
final Dataset<Row> rslt = spark.sql("select * from ds1 JOIN ds2 ON ds1.Name==ds2.CustName");
(using only name)
but it gives output of mXn for m matching rows in ds1 with n matching rows in ds2.
My first work on this. Any suggestion?
I have 2 dimension tables and 1 fact table as follows:
user_dim
user_id
user_name
user_joining_date
1
Steve
2013-01-04
2
Adam
2012-11-01
3
John
2013-05-05
4
Tony
2012-01-01
5
Dan
2010-01-01
6
Alex
2019-01-01
7
Kim
2019-01-01
bundle_dim
bundle_id
bundle_name
bundle_type
bundle_cost_per_day
101
movies and TV
prime
5.5
102
TV and sports
prime
6.5
103
Cooking
prime
7
104
Sports and news
prime
5
105
kids movie
extra
2
106
kids educative
extra
3.5
107
spanish news
extra
2.5
108
Spanish TV and sports
extra
3.5
109
Travel
extra
2
plans_fact
user_id
bundle_id
bundle_start_date
bundle_end_date
1
101
2019-10-10
2020-10-10
2
107
2020-01-15
(null)
2
106
2020-01-15
2020-12-31
2
101
2020-01-15
(null)
2
103
2020-01-15
2020-02-15
1
101
2020-10-11
(null)
1
107
2019-10-10
2020-10-10
1
105
2019-10-10
2020-10-10
4
101
2021-01-01
2021-02-01
3
104
2020-02-17
2020-03-17
2
108
2020-01-15
(null)
4
102
2021-01-01
(null)
4
103
2021-01-01
(null)
4
108
2021-01-01
(null)
5
103
2020-01-15
(null)
5
101
2020-01-15
2020-02-15
6
101
2021-01-01
2021-01-17
6
101
2021-01-20
(null)
6
108
2021-01-01
(null)
7
104
2020-02-17
(null)
7
103
2020-01-17
2020-01-18
1
102
2020-12-11
(null)
2
106
2021-01-01
(null)
7
107
2020-01-15
(null)
note: NULL bundle_end_date refers to active subscription.
user active days can be calculated as: bundle_end_date - bundle_start_date (for the given bundle)
total revenue per user could be calculated as : total no. of active days * bundle rate per day
I am looking to write a query to find revenue generated per user per year.
Here is what I have for the overall revenue per user:
select pf.user_id
, sum(datediff(day, pf.bundle_start_date, coalesce(pf.bundle_end_date, getdate())) * bd.price_per_day) total_cost_per_bundle
from plans_fact pf
inner join bundle_dim bd on bd.bundle_id = pf.bundle_id
group by pf.user_id
order by pf.user_id;
You need a 'year' table to help parse out each multi-year spanning row into it's seperate years. For each year, you need to also recalculate the start and end dates. That's what I do in the yearParsed cte in the code below. I hard code the years into the join statement that creates y. You probably will do it different but however you get those values will work.
After that, pretty much sum as you did before, just adding the year column to your grouping.
Aside from that, all I did was move the null coalesce logic to the cte to make the overall logic simpler.
with yearParsed as (
select pf.*,
y.year,
startDt = iif(pf.bundle_start_date > y.startDt, pf.bundle_start_date, y.startDt),
endDt = iif(ap.bundle_end_date < y.endDt, ap.bundle_end_date, y.endDt)
from plans_fact pf
cross apply (select bundle_end_date = isnull(pf.bundle_end_date, getdate())) ap
join (values
(2019, '2019-01-01', '2019-12-31'),
(2020, '2020-01-01', '2020-12-31'),
(2021, '2021-01-01', '2021-12-31')
) y (year, startDt, endDt)
on pf.bundle_start_date <= y.endDt
and ap.bundle_end_date >= y.startDt
)
select yp.user_id,
yp.year,
total_cost_per_bundle = sum(datediff(day, yp.startDt, yp.endDt) * bd.bundle_cost_per_day)
from yearParsed yp
join bundle_dim bd on bd.bundle_id = yp.bundle_id
group by yp.user_id,
yp.year
order by yp.user_id,
yp.year;
Now, if this is common, you should probably create a base-table for your 'year' table. But if it's not common, but for this report you don't want to have to keep coming back to hard-code the year information into the y table, you can do this:
declare #yearTable table (
year int,
startDt char(10),
endDt char(10)
);
with y as (
select year = year(min(pf.bundle_start_date))
from #plans_fact pf
union all
select year + 1
from y
where year < year(getdate())
)
insert #yearTable
select year,
startDt = convert(char(4),year) + '-01-01',
endDt = convert(char(4),year) + '-12-31'
from y;
and it will create the appropriate years for you. But you can see why creating a base table may be preferred if you have this or a similar need often.
I have a table :
xx_asg
person_no location org mgr_person_no effective_start_date eff_end_date
1 Mumbai XYZ 101 01-jan-1901 01-jan-1990
1 Mumbai XYZ 101 01-JAN-1990 31-DEC-4712
101 Delhi xyz 201 01-JAN-2005 31-DEC-4712
5 Delhi XYZ 1 01-JAN-1901 31-DEC-4712
In this table each person has a manager whose person record is also ther in this table.
But as seen above there are cases like for person no 1 with effective start date 01-jan-1901 but it has a manager person no. 101 whose effective start date is from 01-jan-2005. so this is invalid as from 1901-2005 this manager did not existed.
Now i want to insert a record for person_no. 1 in this table in such a way that mgr person np. 101 gets deleted from 01-jan-1901 to 31-dec-2004 and there is a new record for person_no.1
from 01-jan-2005 to 31-dec-4712
something like :
person_no location org mgr_person_no effective_start_date eff_end_date
1 Mumbai XYZ 01-jan-1901 01-jan-1990
1 Mumbai XYZ 01-JAN-1990 31-DEC-2004
1 Mumbai XYZ 101 01-JAN-2005 31-DEC-4712
101 Delhi xyz 201 01-JAN-2005 31-DEC-4712
5 Delhi XYZ 1 01-JAN-1901 31-DEC-4712