Get all the strictly matching records from two tables

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I have following type of tables

DECLARE @tbStudent TABLE (StudentId INT, StudentName NVARCHAR(100))
INSERT INTO @tbStudent (StudentId , StudentName)
VALUES (101,'James'),(102,'Smith'),(103,'Jackson'),(104,'Peter');

DECLARE @tbStudentCourseDetails TABLE (StudentId INT, CourseId INT)
INSERT INTO @tbStudentCourseDetails (StudentId , CourseId)
VALUES (101,1),(101,3),(101,6),
(102,4),(102,3),
(103,5),(103,3),
(104,1),(104,3),
(105,1);

DECLARE @tbCourseDone TABLE (CourseId INT)
INSERT INTO @tbCourseDone(CourseId)
VALUES (1),(3);

SELECT * FROM @tbStudent
SELECT * FROM @tbStudentCourseDetails
SELECT * FROM @tbCourseDone

Now i need to get the StudentId, StudentName,CourseId records where Student has done all the courses defined in @tbCourseDone table i.e. 1 and 3

Output should be
StudentId StudentName CourseId
101 James 1
101 James 3
104 Peter 1
104 Peter 3

What I have tried:

I tried In operator but it is fetching the records of the student where any course is matched

I also tried below query and got the result i want:

DECLARE @RecCount int=(SELECT count(*) FROM @tbCourseDone)

;WITH myCTE
AS
(
SELECT EM.StudentId
FROM @tbStudent EM
INNER JOIN @tbStudentCourseDetails teld ON EM.StudentId = teld.StudentId
INNER JOIN @tbCourseDone t ON t.CourseId=teld.CourseId
GROUP BY EM.StudentId HAVING COUNT(Em.StudentId)=@RecCount
)

SELECT EM.StudentId,StudentName,teld.CourseId
FROM @tbStudent EM
INNER JOIN @tbStudentCourseDetails teld ON EM.StudentId = teld.StudentId
INNER JOIN @tbCourseDone t ON t.CourseId=teld.CourseId
INNER JOIN myCTE cte ON cte.StudentId=EM.StudentId

But it is not optimized query and can be shorten i think. Please help me in getting this result.

Posted 28-May-19 21:41pm

Webcodeexpert.com

Updated 29-May-19 3:59am

v4

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Richard Deeming · Accepted Answer · 2019-05-29T03:59:00

There might be a simpler way to do this, but the first thing that comes to mind is a double NOT EXISTS test:

SQL

SELECT
    S.StudentId,
    S.StudentName,
    C.CourseId
FROM
    @tbStudent As S
    INNER JOIN @tbStudentCourseDetails As C
    ON C.StudentId = S.StudentId
WHERE
    -- Only return details for the required courses:
    Exists
    (
        SELECT 1
        FROM @tbCourseDone As D
        WHERE D.CourseId = C.CourseId
    )
And
    -- Exclude students who haven't done all required courses:
    Not Exists
    (
        SELECT 1
        FROM @tbCourseDone As D
        WHERE Not Exists
        (
            SELECT 1
            FROM @tbStudentCourseDetails As C2
            WHERE C2.CourseId = D.CourseId
            And C2.StudentId = S.StudentId
        )
    )
ORDER BY
    S.StudentId,
    C.CourseId
;