Consider the following set of relations: EMP(eno, ename, dno) DEPT(dno,dname) Primary key columns are in bold and dno in EMP is a foreign key referring primary key of DEPT table.
Now consider the following queries:
QUERY : 1
SELECT * FROM emp e, dept d WHERE e.dno = d.dno;
QUERY : 2
SELECT * FROM emp NATURAL JOIN dept ;
Then which of the following statements are TRUE regarding the above queries?
emp NATURAL JOIN dept
Q2 has a Natural Join
FROM emp e, dept d WHERE e.dno = d.dno;
FROM emp e, dept d
WHERE e.dno = d.dno;
Q1 has a cross product with equality condition
Both produce the same result for the number rows, but in Cross Product columns would be duplicated, while that won't happen in case of join.
So, I and IV are correct.
Option B
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