I have this tables People, Ticket, and Report.
+----------+-------+-----+
| idPeople | Name | Age |
+----------+-------+-----+
| 1 | Name1 | 21 |
| 2 | Name2 | 37 |
| 3 | Name3 | 28 |
+----------+-------+-----+
I would like to replace the ForeingKey idPeople with columns Name and Age from People table.
+----------+------------+------------+----------+
| idTicket | ticketCol2 | ticketCol3 | idPeople |
+----------+------------+------------+----------+
| 5 | True | 01/06/99 | 1 |
| 6 | False | 01/06/99 | 2 |
| 7 | True | 01/06/99 | 4 |
+----------+------------+------------+----------+
In the Report table replace the Foreing Key idTicket with ticketCol2, Name, Age from the previous table Ticket with replaced columns (idPeople by Name, Age).
+----------+----------+------------+------------+
| idReport | idTicket | ReportCol3 | ReportCol4 |
+----------+----------+------------+------------+
| 1 | 5 | 01/06/99 | blabla |
| 2 | 7 | 01/06/99 | asdfdd |
| 2 | 6 | 01/06/99 | fooboo |
+----------+----------+------------+------------+
And I the result should be like this table and must be done in one query.
+----------+------------+------------+------------+------------+------+-----+
| idReport | ticketCol2 | ticketCol3 | ReportCol3 | ReportCol4 | Name | Age |
+----------+------------+------------+------------+------------+------+-----+
| 1 | 01/06/99 | abcd | blabla | 123456 | Name | 20 |
| 2 | 01/06/99 | bcda | asdfdd | 321456 | Name | 23 |
| 3 | 01/06/99 | asdf | fooboo | 123456 | Name | 28 |
+----------+------------+------------+------------+------------+------+-----+
I Have tried replacing the foreingkeys with LEFT JOIN and bringing some columns Name and Age to the Ticket table but now the last part where I should replace idTicket with Columns from Ticket is not working.
I have read about the nested JOINs but I cannot understand it very well, I would really appreciate some idea of how I can do it or what should I investigate. Are nested Joins the right way?
The query that I’ve tried to accomplish the Table Ticket.
SELECT Ticket.ticketCol2, Ticket.ticketCol3, p.Name 'Name', p.Age 'Age'
from Ticket
left join people p on (Ticket.idPeople=p.idPeople);
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Answer
Try something like this:
SELECT Report.idReport,
Ticket.ticketCol2,
Ticket.ticketCol3,
Report.ReportCol3,
Report.ReportCol4,
People.Name,
People.Age
FROM People
LEFT JOIN Ticket ON Ticket.idPeople = People.idPeople
LEFT JOIN Report ON Report.idTicket = Ticket.idTicket
Like @RiggsFolly said, the Ticket.idPeople
won´t match to the People.idPeople
, so this will not match any rows.