Separate distinct values in to columns - sql

Hi all I am quite new to SQL. I have a table (TABLE1) with two columns as below
Name age
--------
jim 18
jim 21
dave 18
dave 18
john 23
john 41
I need to create a view in SSMS which lists distinct ages for each name in a separate column as below
Jim Dave John
---------------
18 18 23
21 41
I have tried a sub query like
SELECT DISTINCT AGE FROM TABLE1 WHERE NAME = JIM
But I encountered a sub query cannot return more than one value.

You can use row_number() & do aggregation :
select max(case when name = 'jim' then age end) as jim,
max(case when name = 'dave' then age end) as dave,
max(case when name = 'john' then age end) as john
from (select t.*, row_number() over (partition by name order by age) as seq
from table t
) t
group by seq;

Related

How to query: "for which do these values apply"?

I'm trying to match and align data, or resaid, count occurrences and then list for which values those occurrences occur.
Or, in a question: "How many times does each ID value occur, and for what names?"
For example, with this input
Name ID
-------------
jim 123
jim 234
jim 345
john 123
john 345
jane 234
jane 345
jan 45678
I want the output to be:
count ID name name name
------------------------------------
3 345 jim john jane
2 123 jim john
2 234 jim jane
1 45678 jan
Or similarly, the input could be (noticing that the ID values are not aligned),
jim john jane jan
----------------------------
123 345 234 45678
234 123 345
345
but that seems to complicate things.
As close as I am to the desired results is in SQL, as
for ID, count(ID)
from table
group by (ID)
order by count desc
which outputs
ID count
------------
345 3
123 2
234 2
45678 1
I'll appreciate help.
You seem to want a pivot. In SQL, you have to specify the number of columns in advance (unless you construct the query as a string).
But the idea is:
select ID, count(*) as cnt,
max(case when seqnum = 1 then name end) as name_1,
max(case when seqnum = 2 then name end) as name_2,
max(case when seqnum = 3 then name end) as name_3
from (select t.*,
row_number() over (partition by id order by id) as seqnum -- arbitrary ordering
from table t
) t
group by ID
order by count desc;
If you have an unknown number of columns, you can aggregate the values into an array:
select ID, count(*) as cnt,
array_agg(name order by name) as names
from table t
group by ID
order by count desc
the query would look similar to this if that's what you're looking for.
SELECT
name,
id,
COUNT(id) as count
FROM
dataSet
WHERE
dataSet.name = 'input'
AND dataSet.id = 'input'
GROUP BY
name,
id

How to find rows where the same column has only the same another column

Suppose following table:
Name Age Occupation
Alex 20 Student
Alex 20 Seller
Alex 20 Minister
Liza 19 Student
Liza 20 Volunteer
Liza 21 HR partner
I want to find names which have only (and only) 20 in age column. So from this table I want to get all "Alex" rows and no "Liza" rows at all.
Thanks!
You need to use Group By and Having clause. Try this way
select Name
from table
group by Name
having count(case when Age = 20 then 1 end) = count(*)
count(case when Age = 20 then 1 end) counts only when age = 20 if it is equal to total count then the name has only 20 as age.
Just one another way:
select Name
from table
group by Name
having min(Age) = 20 and max(Age) = 20
One way is using NOT IN():
SELECT Name, Age, Occupation
FROM YourTable
WHERE Age = 20
AND Name NOT IN (SELECT Name FROM YourTable WHERE Age <> 20)

How to select only details of min value only in SQL?

I could get the minimum percentage of two values, but I need only the name, and ID in the select.
ID NAME CITY ONE TWO
--------------------------------------------------
2 Morales Los Angeles 40 10
1 John New York 60 20
4 Mary San Diego 10 10
I need to get the min value of one/two, and to only appear this as a result:
ID NAME
---------
4 Mary
Select ID, NAME
from MYTABLE
where least(ONE,TWO) = (select min(least(ONE,TWO)) from MYTABLE);
If you don't want Morales, then you can do this :
Select ID, NAME
from MYTABLE
where id =
(select id from
(select id from MYTABLE order by least(ONE,TWO), ONE*TWO)
where rownum <= 1);

SQL Teradata query

I have a table abc which have many records with columns col1,col2,col3,
dept | name | marks |
science abc 50
science cvv 21
science cvv 22
maths def 60
maths abc 21
maths def 62
maths ddd 90
I need to order by dept and name with ranking as ddd- 1, cvv - 2, abc -3, else 4 then need to find out maximum mark of an individual. Expected result is
dept | name | marks |
science cvv 22
science abc 50
maths ddd 90
maths abc 21
maths def 62
. How may I do it.?
SELECT
dept,
name,
MAX(marks) AS mark
FROM
yourTable
GROUP BY
dept,
name
ORDER BY
CASE WHEN name = 'ddd' THEN 1
name = 'cvv' THEN 2
name = 'abc' THEN 3
ELSE 4 END
Or, preferably, have another table that includes the sorting order.
SELECT
yourTable.dept,
yourTable.name,
MAX(yourTable.marks) AS mark
FROM
yourTable
INNER JOIN
anotherTable
ON yourTable.name = anotherTable.name
GROUP BY
yourTable.dept,
youtTable.name
ORDER BY
anotherTable.sortingOrder
This should work:
SELECT Dept, Name, MAX(marks) AS mark
FROM yourTable
GROUP BY Dept, Name
ORDER BY CASE WHEN Name = 'ddd' THEN 1
WHEN Name = 'cvv' THEN 2
WHEN Name = 'ABC' THEN 3
ELSE 4 END

SQL Group By Help Required

I have a table named People in the following format:
Date | Name.
When I count the people by Grouping By Name with
Select Date, Name, count(*)
From People
Group By Date, Name;
Will give the following
Date Name count(*)
10 Peter 25
10 John 30
10 Mark 25
11 Peter 15
11 John 10
11 Mark 5
But I would like the following result:
Date Peter John Mark
10 25 30 25
11 15 10 5
Is this possible? This is a simple example of a more complicated database. If someone helps me in solving this problem I will use the concept to implement it in my table
Thanks!
Select Date
, count(case when Name = 'Peter' then 1 else null end)
, count(case when Name = 'John' then 1 else null end)
, count(case when Name = 'Mark' then 1 else null end)
From People
Group By Date;
another option different from turbanoff's if, for some reason, you find yourself in a situation that you cant apply a group by:
Select distinct(P.Date),
(select count(*) from People where date=p.date and name='Peter') as Peter,
(select count(*) from People where date=p.date and name='John') as John,
(select count(*) from People where date=p.date and name='Mark') as Mark
From People P