I have 4 types of values in one single column and looking to split those values in 4 different columns using SQL.
This is my table:
Name Car
---------------
John Tesla
John Renault
John Mercedes
John VW
And I would like have this result:
Name Car1 Car2 Car3 Car4
-----------------------------------------
John Tesla Renault Mercedes VW
Can anyone help?
Thanks
You can use PIVOT for this.
Your example almost exactly matches the Microsoft help page, comment if you need more help-
https://technet.microsoft.com/en-us/library/ms177410(v=sql.105).aspx
Right, I figured it out. I didn't realise that when you execute a SELECT function in SQL, you are actually creating a new column. I thought you just merged columns together.
So my code was simply:
SELECT
(CASE WHEN car = "Tesla" THEN name ELSE Null END) as Car_type_1
(CASE WHEN car = "Renault" THEN name ELSE Null END) as Car_type_2
(CASE WHEN car = "Mercedes" THEN name ELSE Null END) as Car_type_3
(CASE WHEN car = "VW" THEN name ELSE Null END) as Car_type_4
Should have learnt the basics of SQL! Hope this helps anybody else in my situation.
Related
I have table, and I need to find out the person name who dont have Iphone?
Ex. query should give from the below table as Mike.
I am trying to built logic using group by on name and Items where Item not equal to Iphone or by using 2 table but unable to get the result, can anyone suggest ?
Name
Items
Simon
Iphone
Simon
Tablate
Simon
Watch
Simon
Laptop
Jim
Iphone
Jim
Tablate
Jim
Watch
Jim
Laptop
Mike
Tablate
Mike
Watch
Mike
Laptop
I have table, and I need to find out the person name who dont have Iphone?
Using your table, you can use aggregation:
select name
from t
group by name
having sum(case when item = 'Iphone' then 1 else 0 end) = 0;
The having clause counts the number of rows with iphones. The = 0 says there are none for the name.
I like gordons answer but this might be easier to understand:
select name
from table
where name not in
(select name
from table
where item like 'Iphone')
If you need only a single record for each name go for this at the end:
group by name
I am trying to count how many makes of car a person owns. Car makes are only defined by a prefix in my Links table.
Table 1 (Person)
UniqueID Name
PER0001 Adrian
PER0002 Michael
Per0003 James
Table 2 (Links)
UniqueID LinkEnd1_ID LinkEnd2_ID
LIN0001 PER0001 FER02332
LIN0002 PER0001 FER02112
LIN0003 PER0001 POR12122
LIN0004 PER0002 FER12321
LIN0005 PER0003 MAS12382
LIN0006 PER0003 FER22982
LIN0006 PER0003 MAS12232
Output (option 1)
Name Car_Make Count
Adrian FER 2
Adrian POR 1
Michael FER 1
James MAS 2
James FER 1
Output (option 2 - preferred)
Name FER POR MAS
Adrian 1 2
Michael 1
James 1 2
The reason I am using a link table to count the number of car makes is because every car make has a different table I would need to join in.
I've tried
select count left(LinkEnd2_ID,3) which doesnt work, i've also tried group by which I cant seem to crack.
I guess what I want to be able to do is
select
count(left(LinkEnd2_ID,3)='FER'
,count(left(LinkEnd2_ID,3)='POR'
,count(left(LinkEnd2_ID,3)='MAS'
but thats a query in a select and I decipher how to code that properly.
Heres where I am starting from (or the base I keep going back to start afresh)-
SELECT
Person.Unique_ID
,Person.Name
,left(Link.LinkEnd2_ID,3) as Car_Make
FROM
Person
LEFT JOIN
Links as Link
on Person.Unique_ID = Link.LinkEnd1_ID
Any help you can offer would be appreciated.
Nearly there, you just need to add a group by, and change all the columns to aggregate functions.
Your option 1:
SELECT
max(Person.Name) as Person_Name
,left(Link.LinkEnd2_ID,3) as Car_Make
,count(*) as No_of_Car
FROM
Person
LEFT JOIN
Links as Link
on Person.Unique_ID = Link.LinkEnd1_ID
GROUP BY
Person.Unique_ID
For your option 2, you need to wrap your aggregate functions around case statements
you have to hardcode the 3 different car make, so if you have unknown number of them, it wouldn't work.
SELECT
max(Person.Name) as Person_Name
,sum(case when left(Link.LinkEnd2_ID,3) ='FER' then 1 else 0 end) as FER
,sum(case when left(Link.LinkEnd2_ID,3) ='POR' then 1 else 0 end) as POR
,sum(case when left(Link.LinkEnd2_ID,3) ='MAS' then 1 else 0 end) as MAS
FROM
Person
LEFT JOIN
Links as Link
on Person.Unique_ID = Link.LinkEnd1_ID
GROUP BY
Person.Unique_ID
Due to the way a particular table is written I need to do something a little strange in SQL and I can't find a 'simple' way to do this
Table
Name Place Amount
Chris Scotland
Chris £1
Amy England
Amy £5
Output
Chris Scotland £1
Amy England £5
What I am trying to do is above, so the null rows are essentially ignored and 'grouped' up based on the Name
I have this working using For XML however it is incredibly slow, is there a smarter way to do this?
This is where MAX would work
select
Name
,Place = Max(Place)
,Amount = Max(Amount)
from
YourTable
group by
Name
Naturally, if you have more than one occurance of a place for a given name, you may get unexpected results.
Not the best title hence why I was unable to find a solution that would fix mine, point me in the direction if you know of one.
Currently I have the below query,
SELECT PRODUCT_NAME
,LIVE
,LOCATION
FROM PRODUCT_TABLE
WHERE ORDER = 'ONLINE'
AND LIVE = '0' OR '1'
This essentially is a really simple query that pulls back a lot of data in which I've been using Excel to drill down to what I need however as I'm sure you can imagine a really tedious process so preferably prefer to do it straight with SQL as I know it can be done just my knowledge has completely disappeared after not using it in a while.
But essentially what I'm wanting to achieve is looking for all products online that are live at a location (0 means YES in the above query) and have matching product name at another location that isn't live (in this case not live = 1).
For example below is some data that is formatted in a similar sort of way.
LOCATION LIVE PRODUCT_NAME
BERLIN 0 CHAIR
LONDON 1 CHAIR
PARIS 0 LAMP
PARIS 0 SOFA
WARSAW 1 CHAIR
MADRID 0 CHAIR
MANCHESTER 1 SOFA
If someone could provide a solution or point me in the right direction that would be great, thanks!
You want something like this:
select pt.*
from product_table pt
where pt.live = '0' and
exists (select 1
from product_table pt2
where pt2.product_name = pt.product_name and
pt2.location <> pt.location and
pt2.live = '1'
);
SELECT DISTINCT
pt.PRODUCT_NAME
,pt.LIVE
,pt.LOCATION
FROM PRODUCT_TABLE pt
LEFT JOIN PRODUCT_TABE pt2
on pt.NAME = pt2.NAME
AND pt2.LIVE = 1
AND pt.LOCATION != pt2.LOCATION
WHERE pt.ORDER = 'ONLINE'
AND pt.LIVE = '0'
AND pt2.NAME IS NOT NULL
I have taken a good look around and not been able to find any questions that match mine. Maybe I am not using the right language when searching or whatever, but here goes.
I have an SQL table called Classes that looks something like this
Student_Name | Class
--------------------
Edgar | Chemistry
Allan | Chemistry
Burt | Chemistry
Edgar | Math
Sue | Math
Hamilton | Math
Edgar | English
Sue | English
Edgar | German
Ben | German
I want to count how many students are taking both Math and German.
Assuming the following in this example:
- Student names are unique
- One student can have many classes
Logically I would use a select statement to get a result set of students who are taking Math. Then I would go through each Student_Name from the result set and check them against the table to see how many are taking German.
In this case I would expect a return of 1 as only Edgar is taking both Math and German.
Here are some of the queries I have tried so far to no avail :-(
This one was after doing some research on DISTINCT:
SELECT COUNT(DISTINCT Student_Name) FROM Classes WHERE Class = 'Math' AND Class = 'German';
And this one was after finding out more about GROUP BY:
SELECT COUNT(*) FROM (
SELECT DISTINCT Student_Name FROM Classes
WHERE Class IN ( 'Math', 'German' )
GROUP BY Student_Name
);
Neither of these came out quite right any help would be highly appreciated.
SELECT COUNT(*) totalStudent
FROM
(
SELECT student_name
FROM Classes
WHERE class IN ('Math','German')
GROUP BY student_name
HAVING COUNT(*) = 2
) subAlias
SQLFiddle Demo
OUTPUT
╔══════════════╗
║ TOTALSTUDENT ║
╠══════════════╣
║ 1 ║
╚══════════════╝
Could also do the following:
select count(distinct a.Student_name)
from Classes a inner join Classes b on
a.Class = 'German' and
b.Class = 'Math' and
a.Student_Name = b.Student_name;
This solves the problem where the table contains duplicate rows (as pointed out by a commenter to another answer)