Question

I have two tables Like Below

CREATE TABLE projectlist(ProjectId   INT NOT NULL PRIMARY KEY,
                         ProjectName VARCHAR(50),
                         Location    VARCHAR(50));

CREATE TABLE LocationList(LocaId INT NOT NULL PRIMARY KEY AUTO_INCREMENT,
                          ProjectId INT,
                          Location    VARCHAR(50));

The Values in the table are as Below

INSERT INTO projectlist(ProjectId, ProjectName)
                 VALUES(1, 'Project A'),
                       (2, 'Project B'),
                       (3, 'Project C'),
                       (4, 'Project D'),
                       (5, 'Project E'),
                       (6, 'Project F'),
                       (7, 'Project G'),
                       (8, 'Project H');

INSERT INTO LocationList(ProjectId, Location)
                  VALUES(1, 'Location A'),
                        (1, 'Location C'),
                        (2, 'Location C'),
                        (2, 'Location B'),
                        (2, 'Location A'),
                        (3, 'Location B'),
                        (4, 'Location C'),
                        (5, 'Location D'),
                        (6, 'Location A'),
                        (6, 'Location B'),
                        (7, 'Location B'),
                        (8, 'Location D'),
                        (8, 'Location A');

I want a Insert Query which inserts First LocationList.Location into projectlist.Location for their respective project relating on project id.

So the table projectlist after running query is

   ProjectName                 Location
    Project A                 Location A 
    Project B                 Location C
    Project C                 Location B
    Project D                 Location C
    Project E                 Location D
    Project F                 Location A
    Project G                 Location B
    Project H                 Location D    

I tried a SQL query which bring the First Location from LocationList table as below.

 SELECT DISTINCT MNPCL.Location, MNP.ProjectId
   FROM LocationList MNPCL RIGHT OUTER JOIN
        projectlist MNP ON MNP.ProjectId = MNPCL.ProjectId                            
  GROUP BY MNP.ProjectName

How to write a query which perform insert in the projectlist Location

Thanks For Reply

Answer 1

Here is a SQLFiddle demo

update projectlist 
join 
(
select LocationList.ProjectID,LocationList.Location 
  from LocationList
join 
(select LocationList.ProjectID,min(LocaId) minLocaId 
    from LocationList 
    group by LocationList.ProjectID) l1
        on LocationList.LocaId=l1.minLocaID
 ) l2 on projectList.ProjectID=l2.ProjectID
SET ProjectList.Location=l2.Location