Repeat the procedure in question 2 for the unordered tables in Fig XXXXXXXXXXSatisfy yourself that repeated scans of a table are necessary. question 2 Query Plan 2 uses a sort-merge join. Fig. 18.8...

Repeat the procedure in question 2 for the unordered tables in Fig. 18.6. Satisfy yourself that repeated scans of a table are necessary.

question 2

Query Plan 2 uses a sort-merge join. Fig. 18.8 shows the Student and Option tables sorted into ascending order of studentNo. Satisfy yourself that the sorted tables can be joined by reading each row only once. Cover the rows in Student with one piece of paper and the rows in Option with another. To read a row, slide a card down. Write down each joined row, assuming a natural join.