Table:
0
A
B
C
D
E
F
1
a id
user id
item id
rating
rank
review
2
1
1
1
10
1
3
2
2
1
5
2
4
3
1
4
7
3
5
4
2
7
10
7
6
5
2
5
7
4
7
6
1
3
5
5
8
7
2
7
6
6

Questions and formulas:
Question: Find the number of reviews.
Formula: ROWS(UNIQUE(F1))
Formula2: ROWS(UNIQUE(F2:F8))
Level: easy
Question: Find the highest rank of all reviews.
Formula: MIN(E1)
Formula2: MIN(E2:E8)
Level: easy
Question: How many different users wrote some reviews?
Formula: ROWS(UNIQUE(B1))
Formula2: ROWS(UNIQUE(B2:B8))
Level: easy
Question: total quantity of reviews
Formula: ROWS(UNIQUE(F1))
Formula2: ROWS(UNIQUE(F2:F8))
Level: easy
Question: Which review is ranked highest?
Formula: TAKE(SORT(SUMMARIZE(F1,SUMX(E1)), 2, 1), 1)
Formula2: TAKE(SORT(SUMMARIZE(F2:F8,SUMX(E2:E8)), 2, 1), 1)
Level: hard
Question: Number of users and number of reviews written by them respectively 
Formula: HSTACK(SUM(B1), ROWS(UNIQUE(F1)))
Formula2: HSTACK(SUM(B2:B8), ROWS(UNIQUE(F2:F8)))
Level: hard
Question: How many reviews?
Formula: ROWS(UNIQUE(F1))
Formula2: ROWS(UNIQUE(F2:F8))
Level: easy
Question: Which is the highest rank of all reviews?
Formula: TAKE(SORT(SUMMARIZE(F1,SUMX(E1)), 2, 1), 1)
Formula2: TAKE(SORT(SUMMARIZE(F2:F8,SUMX(E2:E8)), 2, 1), 1)
Level: hard
Question: How many users and reviews written by them?
Formula: HSTACK(SUM(B1), ROWS(UNIQUE(F1)))
Formula2: HSTACK(SUM(B2:B8), ROWS(UNIQUE(F2:F8)))
Level: hard