Putting it all together

match (n) detach delete n;

create (n:Student{id:101,firstname:"Rachel",lastname:"Green",gender:"F",dob:"2000-01-01"});
create (n:Student{id:102,firstname:"Monica",lastname:"Geller",gender:"F",dob:"2000-02-01"});
create (n:Student{id:103,firstname:"Ross",lastname:"Geller",gender:"M",dob:"1999-01-05"});
create (n:Student{id:104,firstname:"Chandler",lastname:"Bing",gender:"M",dob:"1999-02-07"});
create (n:Student{id:105,firstname:"Phoebe",lastname:"Buffay",gender:"F",dob:"1998-03-07"});
create (n:Student{id:106,firstname:"Joey",lastname:"Tribianni",gender:"M",dob:"1999-07-08"});
create (n:Student{id:107,firstname:"Janice",gender:"F",dob:"2000-07-08"});

CREATE CONSTRAINT cons_stuid_notnull IF NOT EXISTS FOR (n:Student) REQUIRE n.id IS NOT NULL;
CREATE CONSTRAINT cons_stuid_unique IF NOT EXISTS FOR (n:Student) REQUIRE n.id IS UNIQUE; 
create (n:Student{id:108,firstname:"Gunther",gender:"M",dob:"1995-07-08"});

create (t:Course{id:"C001",name:"Applied DB"});
create (t:Course{id:"C002",name:"Big Data"});
create (t:Course{id:"C003",name:"Data Warehousing"});
create (t:Course{id:"C004",name:"Web Programming"});
create (t:Course{id:"C005",name:"Rust Programming"});

create (z:Faculty{id:"F001",firstname:"Ganesh",lastname:"Chandra"});
create (z:Faculty{id:"F002",firstname:"Jack",lastname:"Myers"});
create (z:Faculty{id:"F003",firstname:"Tony",lastname:"Brietzman"});

MATCH (a:Student),(b:Course),(c:Faculty) WHERE a.id = 101 AND b.id = 'C001' AND c.id='F001'
MERGE (c)-[:TEACHING]->(b)
MERGE (b)<-[:TAKING {grade:"A",semester:"Fall2021"}]-(a);

MATCH (a:Student),(b:Course),(c:Faculty) WHERE a.id = 101 AND b.id = 'C003' AND c.id='F003'
MERGE (c)-[:TEACHING]->(b)
MERGE (b)<-[:TAKING {grade:"B",semester:"Spring2022"}]-(a);

MATCH (a:Student),(b:Course),(c:Faculty) WHERE a.id = 102 AND b.id = 'C001' AND c.id='F001'
MERGE (c)-[:TEACHING]->(b)
MERGE (b)<-[:TAKING {grade:"B+",semester:"Spring2022"}]-(a);


MATCH (a:Student),(b:Course),(c:Faculty) WHERE a.id = 101 AND b.id = 'C003' AND c.id='F003'
MERGE (c)-[:TEACHING]->(b)
MERGE (b)<-[:TAKING {grade:"B",semester:"Spring2022"}]-(a);

MATCH (a:Student),(b:Course),(c:Faculty) WHERE a.id = 103 AND b.id = 'C003' AND c.id='F003'
MERGE (c)-[:TEACHING]->(b)
MERGE (b)<-[:TAKING {grade:"A-",semester:"Spring2022"}]-(a);

MATCH (a:Student),(b:Course),(c:Faculty) WHERE a.id = 104 AND b.id = 'C004' AND c.id='F002'
MERGE (c)-[:TEACHING]->(b)
MERGE (b)<-[:TAKING {grade:"A",semester:"Fall2021"}]-(a);

MATCH (a:Student),(b:Course),(c:Faculty) WHERE a.id = 105 AND b.id = 'C005' AND c.id='F001'
MERGE (c)-[:TEACHING]->(b)
MERGE (b)<-[:TAKING {grade:"A",semester:"Spring2022"}]-(a);

MATCH (a:Student),(b:Course),(c:Faculty) WHERE a.id = 106 AND b.id = 'C004' AND c.id='F001'
MERGE (c)-[:TEACHING]->(b)
MERGE (b)<-[:TAKING {grade:"B+",semester:"Fall2021"}]-(a);

MATCH (a:Student),(b:Course),(c:Faculty) WHERE a.id = 106 AND b.id = 'C002' AND c.id='F002'
MERGE (c)-[:TEACHING]->(b)
MERGE (b)<-[:TAKING {grade:"A",semester:"Spring2022"}]-(a);

MATCH (a:Student),(b:Course),(c:Faculty) WHERE a.id = 107 AND b.id = 'C005' AND c.id='F001'
MERGE (c)-[:TEACHING]->(b)
MERGE (b)<-[:TAKING {grade:"A",semester:"Fall2021"}]-(a);

Queries

1. Retrieve All Students

MATCH (n:Student) RETURN n;

2. Find a Specific Student by ID

MATCH (n:Student {id:101}) RETURN n;

3. List All Courses

MATCH (n:Course) RETURN n.name;

4. Find Students Taking a Specific Course

MATCH (s:Student)-[:TAKING]->(c:Course {id:"C001"}) 
RETURN s.firstname, s.lastname;

5. List Courses Taught by a Specific Faculty

MATCH (f:Faculty {id:"F001"})-[:TEACHING]->(c:Course) 
RETURN f.firstname, f.lastname, collect(c.name) AS Courses;

6. Find Students and Their Grades for a Specific Course

MATCH (s:Student)-[r:TAKING]->(c:Course {id:"C002"}) 
RETURN s.firstname, s.lastname, r.grade;

7. Find Average Grade for Each Course

MATCH (s:Student)-[r:TAKING]->(c:Course) 
RETURN c.name, avg(toFloat(r.grade)) AS AverageGrade
ORDER BY AverageGrade DESC;

8. Identify Students Taking Courses with a Specific Faculty

MATCH (s:Student)-[:TAKING]->(c:Course)<-[:TEACHING]-(f:Faculty {id:"F001"}) 
RETURN s.firstname, s.lastname, collect(c.name) AS Courses;

9. Create a Friendship Relationship Between Students

MATCH (s1:Student {id:101}), (s2:Student {id:102}) 
MERGE (s1)-[:FRIENDS_WITH]->(s2);

Creates a "FRIENDS_WITH" relationship between two students.

10. Find Students and the Number of Courses They Are Taking

MATCH (s:Student)-[:TAKING]->(c:Course) 
RETURN s.firstname, s.lastname, count(c) AS CoursesTaken
ORDER BY CoursesTaken DESC;

Counts how many courses each student is taking.

11. Find the Most Popular Course

MATCH (s:Student)-[:TAKING]->(c:Course) 
WITH c, count(s) AS StudentCount 
ORDER BY StudentCount DESC 
LIMIT 1 
RETURN c.name, StudentCount;

12. Students and Their Friends Taking the Same Course

MATCH (s:Student)-[:FRIENDS_WITH]->(friend:Student)-[:TAKING]->(course:Course), (s)-[:TAKING]->(course) 
RETURN s.firstname, friend.firstname, course.name;

13. Search by Semester & Grade

MATCH (s:Student)-[r:TAKING]->(c:Course) 
WHERE r.semester = "Spring2022" 
AND r.grade =~ "[A-C].*|D+" 
RETURN s.id AS StudentID, s.firstname AS FirstName, s.lastname AS LastName, c.id AS CourseID, c.name AS CourseName, r.grade AS Grade

14. Show all connected nodes for a given node (upto 4 levels)

MATCH (ross:Student {firstname:"Ross"})-[*1..4]-(connectedNodes)
RETURN ross, connectedNodes;

15. Show all connected nodes

MATCH (ross:Student {firstname:"Ross"})-[*1..]-(connectedNodes)
RETURN ross, connectedNodes;