Considering these two tables:
Position(positionid, positiontext, reportstopositionid)
User(userid, positionid)
How can I check if a user has any subordinates in one query?
Is it even possible?
A subordinate:
user (a) with positionid has at least one or more subordinates if there exists any users (b) with the positionid of user (a) as reportstopositionid to users (b) corresponding positionid
This will return users who have subordinates:
SELECT *
FROM User u
WHERE EXISTS (
SELECT 1
FROM Position p
WHERE p.reportstopositionid = u.positionid
)
how about this one?
SELECT DISTINCT a.*
FROM user a
INNER JOIN position b
ON a.userID = b.reportstopositionID
the records returned by this query are those which has matching IDs userid on position table at column reportstopositionID
I think you want to do this with a where clause:
select u.*
from user u
where u.positionId in (select reportstopositionid from position p)
This gets the list of users who match, without duplicates.
Related
I have the following table "Friends":
The goal is to find out how many users have the exact same list of friends.
In this case, the result would be user_id 1 and user_id 4 since both user 1 and user 4 are friends with "2" and "3".
I think I am on the right track by using the code below:
SELECT * FROM Friends A, Friends B WHERE A.friend_id=B.friend_id AND A.user_id <> B.user_id
However, I am not able to figure out how to finish the query so that it calculates the matching list of friends. Does anyone have any suggestions?
You didn't provide your SQL type.
For MySQL, you can group concat the friends for every user and cross by this value. The default is ",". Then join the same table to compare by the same list of friends.
SELECT t1.friends, t1.friends FROM
(
SELECT user_id,GROUP_CONCAT(friend_id) as friends
FROM friends
GROUP BY friend_id
) as t1
JOIN
(
SELECT user_id,GROUP_CONCAT(friend_id) as friends
FROM friends
GROUP BY friend_id
) as t2
on t1.friends = t2.friends
Ok, so I have a table Assignment:
[UserId]
[GroupId]
[UpdatedBy]
[UpdatedAt]
Also, I have a function for returning users from a specific group:
select UserId
from dbo.GetGroupUsers() ggu
where ggu.GroupId = ?
In Assignment, I want to check all groups that our user is listed and then I want to select ALL users from these groups, without duplicate.
How can I achieve this?
Edit:
Sample output form selecting groupid = 4
for example user "test1" belong to other group where id=2 at the same time and i want selected all users from for example group 2 and 4 (cause in this example test1 said so) without records duplicate
All groups from one UserId (say UserId 10):
select GroupId from Assignment where UserId = 10
Select all users from those groups (without duplicate):
select distinct UserId
from dbo.GetGroupUsers() ggu
where ggu.GroupId in (select GroupId from Assignment where UserId = 10)
I hope this is what you wanted.
An inner self join should get you the IDs of the users you're looking for. Join the result with your user table (which you didn't post) to possibly get other information about these users.
SELECT DISTINCT
a2.userid
FROM assignment a1
INNER JOIN assignment a2
ON a2.groupid = a1.groupid
WHERE a1.userid = ?;
(Replace the ? with the ID of the user, you want to start with.)
Assuming your input is a user id:test1 and assuming that you are just looking at one table (Assignment)
DECLARE #UserId INT = 2
;WITH GROUPS AS
(
SELECT DISTINCT GroupId FROM Assignment WHERE UserId = #UserId
)
SELECT distinct assgn.UserName, gps.GroupId FROM Assignment assgn
INNER JOIN
GROUPS gps ON
assgn.GroupId = gps.GroupId
Please let me know if this helps
I got 3 tables, Users, courses and course realation tables. I want to get users who aren't on specific course. So I figure I need somehow merge 2 selects with right join. How could I make one select from 2 selects?
SELECT ID, NAME, LASTNAME, ROLE FROM COURSERELATION JOIN USERS ON
ID_USER = ID WHERE ID_COURSE = ?
RIGTH JOIN
SELECT ID, NAME, LASTNAME, ROLE from COURSERELATION JOIN USERS ON
ID_USER = ID WHERE ID_COURSE != ?
You need to extract users for which it doesn't exist a record of that user for the specific course. You can filter the rows using a NOT EXISTS clause over a subquery.
Please try below query:
SELECT u.ID,
u.NAME,
u.LASTNAME,
u.ROLE
FROM USERS u
WHERE NOT EXISTS (SELECT 1
FROM COURSERELATION s
WHERE s.id_user = u.id
AND s.id_course = 'YOUR_COURSE_ID_HERE' )
i have a User table which has many users but some users are having same first name and Last Name but only one user will have status active . So my requirement is if the user is unique i need the user regardless of Status but if the user is duplicate i need the record having status active.
How can i achieve this in SQL server?
Sorry For the confusion here is the example of User table
my result table should be
Here Steve Jordan is having 2 records so i need the record having status 1
and for records having distinct First name and last name i need all the records regard less of status.
Note : I have a user id as primary key but i am joining on first name and last name because other table doesn't have user id.
SELECT UserId, FirstName, LastName, Status FROM (
SELECT *
, ROW_NUMBER() OVER (PARTITION BY FirstName, LastName
ORDER BY Status DESC) AS rowNum
FROM [User]
) u
WHERE u.rowNum = 1
This essentially groups by first and last name, orders by Status so that active are higher priority, and takes only one of each unique first/last name combination. This ensures that each each unique first/last name combination is in the result set only once, and if there are multiples, the active one is the one returned. If a name combination has multiples, but they are all not active, then only one is returned, chosen arbitrarily.
Ideally, you should have the User ID PK in both tables, as this is much stronger relationally.
EDIT: A bit more complex, but this should give you what you're looking for.
SELECT *
FROM YourOtherTable A
JOIN Users B
ON A.FirstName = B.FirstName AND A.FirstName = B.FirstName
LEFT JOIN
(
SELECT FirstName, LastName FROM User GROUP BY FirstName, LastName HAVING COUNT(FirstName) = 1
) C
ON B.FirstName = C.FirstName AND B.LastName = C.LastName
WHERE B.Status = 1 OR C.FirstName IS NOT NULL
I didn't get you question. But, as per your subject line. It seems like you want the record, which is active, if record is duplicate.
select T.* from yourTable T INNER JOIN (select user, count(*) cnt FROM yourTable GROUP BY user) A ON A.user=T.user
WHERE A.cnt>1 and T.status='A';
If it wasn't your requirement. Then, I would ask you to share your table structure and expected output to understand better.
I have 3 tables in my system: Courses, Scores and Users. Scores is a table which has the test results for each course and each user. So I have the ScoreID, The CourseID the UserID and the Score itself.
I want to show in some page the list of courses that the user didn't finished yet. So I want it to show all the courses excluding those the user has records in the Scores table (meaning he already has finished it).
How do I exclude the rows from a SELECT statement when certain CourseID and UserID match at the same time?
Assuming that this is for just one user, Mark Bannister's answer can be simplified a little...
SELECT
*
FROM
Courses
WHERE
NOT EXISTS (SELECT * FROM Scores WHERE CourseID = Courses.CourseID AND UserID = #userID)
Try:
select *
from Courses c
cross join Users u
where not exists
(select null from Scores s where s.CourseID = c.CourseID and s.UserID = u.UserID)
select *
from Courses
where not exists
(
select null from Scores where Scores.CourseID = Courses.CourseID
and Scores.UserID = Courses.UserID
)
Assuming you are using SQL Server you can
CROSS APPLY the courses and users, creating every possible combinations of courses and users
use NOT EXISTS to filter out those records where a UserID exists.
SQL Statement
SELECT *
FROM Courses c
CROSS APPLY Users u
WHERE NOT EXISTS (
SELECT *
FROM Scores
WHERE UserID = u.UserID
AND ScoreID = c.ScoreID
)
In case you are using any other DBMS, following should work on most DBMS's
SELECT *
FROM Courses AS c
, Users AS u
WHERE NOT EXISTS (
SELECT *
FROM Scores
WHERE UserID = u.UserID
AND ScoreID = c.ScoreID
)