Dynamic transponation of a table

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Hello,

I have a uestion regarding my SQL Code.
My goal is it to switch rows to columns.

ID | NAME | POINTS| DATE
-----------------------------------
1 | KARL | 2 | 2020-05-15
2 | EVA | 0 | 2020-05-15
3 | OTTO | 5 | 2020-05-15
4 | KARL | 3 | 2020-05-16
5 | EVA | 1 | 2020-05-16
6 | OTTO | 7 | 2020-05-16
7 | KARL | 5 | 2020-05-17
8 | EVA | 3 | 2020-05-17
9 | OTTO | 10 | 2020-05-17


Goal:
Name|POINTS|2020-05-15|2020-05-16|2020-05-17
----------------------------------------------------------
KARL|2|3|5
EVA|0|1|3
OTTO|5|7|10

My Code
SELECT
    myname,
    SUBSTRING_INDEX(group_concat(concat(`points`) separator '|'), '|', 1) AS firstday,
    SUBSTRING_INDEX(SUBSTRING_INDEX(group_concat(concat(`points`) separator '|'), '|', 2), '|', -1)  as secondday,  
    SUBSTRING_INDEX(SUBSTRING_INDEX(group_concat(concat(`points`) separator '|'), '|', 3), '|', -1) AS lastday
FROM
    (select * from mytable where mydate >= '2020-05-15' order by myname, mydate) tmp
group by myname

That works, I think with this code.
I want to add a new colum to the table like TEAMS

ID | NAME | TEAM |POINTS| DATE
-----------------------------------
1 | KARL | TEAM1 | 2 | 2020-05-15
2 | EVA | TEAM2 | 0 | 2020-05-15
3 | OTTO | TEAM3 | 5 | 2020-05-15
4 | KARL | TEAM1 | 3 | 2020-05-16
5 | EVA | TEAM2 | 1 | 2020-05-16
6 | OTTO | TEAM3 | 7 | 2020-05-16
7 | KARL | TEAM2 | 5 | 2020-05-17
8 | EVA | TEAM2 | 3 | 2020-05-17
9 | OTTO | TEAM3 | 10 | 2020-05-17

So the output should look like this
Name|TEAM||POINTS|2020-05-15|2020-05-16|2020-05-17
----------------------------------------------------------
KARL|TEAM2|2|3|5
EVA|TEAM2|0|1|3
OTTO|TEAM3|5|7|10

With my code this i snot working correctly. The change of the teams leads to the problem that the new team does not appear and the points are not correct selected.
It selects the last 3 values for the points, but puts the current value for the points to that date, when the change was done.

Like this

Name|TEAM||POINTS|2020-05-15|2020-05-16|2020-05-17
----------------------------------------------------------
KARL|TEAM2|5|3|5


I hope I explained it correct.

I try to have a flexible selection so that changes of the team won't disturb the display of the points.

Thank you very much

With kind regards

Tobi

What I have tried:

Checked manuel for stored procedures

Posted 3-Jun-20 21:29pm

Member 14852988

Updated 5-Jun-20 7:53am

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Comments

Garth J Lancaster 4-Jun-20 4:41am

I think you need to improve your question a little - for instance, why is TEAM2 the Team for Karl here "KARL|TEAM2|2|3|5" ? - ok, it appears to be the last team Karl was in by date or the Max by date ..

Right now I can't see a single query that would do as you ask, I can think of getting a distinct list of names & last team name by date, then using a cursor to iterate through the records for a team member to build the points & dates sections

btw - wtf is 'transponation' ? do you mean 'transposition' perhaps ?

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Member 14852988 · Accepted Answer · 2020-06-05T07:55:00

Hello,

sorry for the wrong posting.
I tried the hole day and I think I found what I am looking for.

SELECT id, name, team, 
                                MAX(CASE WHEN datum = DATE_SUB(CURDATE(), INTERVAL 4 day) THEN points END) 4tage, 
                                MAX(CASE WHEN datum = DATE_SUB(CURDATE(), INTERVAL 3 day) THEN points END) 3tage, 
                                MAX(CASE WHEN datum = DATE_SUB(CURDATE(), INTERVAL 2 day) THEN points END) 2tage, 
                                MAX(CASE WHEN datum = DATE_SUB(CURDATE(), INTERVAL 1 day) THEN ppoints END) 1tage,
                                MAX(CASE WHEN datum = DATE_SUB(CURDATE(), INTERVAL 0 day) THEN points END) 0tage 
                                FROM `vs_highscore` WHERE datum BETWEEN DATE_SUB(NOW() , INTERVAL 5 day) AND NOW() 
                                GROUP BY name, team ORDER BY team DESC

It is not perfect, but for me it is OK.

Perhaps an experts can tell me what to improve.

I found the solution with the link

#realJSOP

posted.
Than you for that.

With kind regards

Tobi

#realJSOP · Accepted Answer · 2020-06-04T01:26:00

Solution 1

What you want to do is perform a "pivot" on your table. If you're doing in it in a MySQL Server view or stored proc, SQL Pivot in all databases: MySQL, MariaDB, SQLite, PostgreSQL, Oracle, …[^]

Posted 4-Jun-20 1:26am

#realJSOP

v2

Comments

Maciej Los 5-Jun-20 14:00pm

5ed!