Assertion. The join, in which columns are compared for equality, is called an Equi-join.

Reason. In non-equi joins, the columns are compared with non-equality conditional operators.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Assertion. There can be joins where all records from one of tables appear irrespective of their matching rows in the other table.

Reason. In LEFT JOIN, all rows from the left table appear in the result along with matching rows from the right table and NULL for the non-matching rows ; and same for the RIGHT JOIN where all rows came from the right table appear, along with only matching rows from the left table.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Assertion. The MINUS and INTERSECT operators are similar.

Reason. The MINUS operator returns only the rows from the first result set while INTERSECT returns the common rows of both the result sets.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

What is Cartesian product ? How is it related to join ?