How to find number of student who participated in the more than single project(in sql)?

Question

Consider the student-project database.
STUDENT
STUDENT NO TEXT (3) PRIMARYKEY
STUDENT_NAME TEXT (10)
STUDENT_DOB DATE
STUDENT_DOJ DATE

PROJECT
PRJ_NO TEXT (3) PRIMARY KEY
PRJ_NAME TEXT (15)
PRJ_DUR NUMBER (2)
PRJ_PLATFORM TEXT (10)

STUDENT PROJECT
STUDENT_NO TEXT (3)
PRJ_NO TEXT (3)
DESIGNATION TEXT (10)
PRIMARYKEY (STUDENT_NO,PRJ_NO,DESIGNATION)
FOREIGN KEY(STUDENT_NO)
FOREIGN KEY(PRJ_NO)

Answer 1

Maybe something like this could work:

select count(*)
from STUDENT_PROJECT
group by STUDENT_NO
having COUNT(PRJ_NO) > 1;