Suppose this was the definition definition of your table and want to load data to it. For this example, we assume data are already validated - -- pre-validation is a central concept in bulk loading.
Present State
Here is what was already in the exam table.
=> select * from exam ;
    fn     |   ln   | exam | score
-----------+--------+------+-------
 tambouras | vena   |    4 |    97
 sun       | ugjn   |    6 |    82
The TaskSuppose we need to load new data and erase old data.
SOLUTION