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Exercise 4:571.Find Median Given Frequency of Numbers

1 Description

TThe Numbers table keeps the value of number and its frequency.
+----------+-------------+
| Number | Frequency |
+----------+-------------|
| 0 | 7 |
| 1 | 1 |
| 2 | 3 |
| 3 | 1 |
+----------+-------------+
In this table, the numbers are 0, 0, 0, 0, 0, 0, 0, 1, 2, 2, 2, 3, so the median is (0 + 0) / 2 = 0.
+--------+
| median |
+--------|
| 0.0000 |
+--------+
Write a query to find the median of all numbers and name the result as median.

2 Create Table and insert into values

create table if not exists leetcode.ex_571_number
(
number int,
frequency int
) stored as orc ;
​
INSERT INTO table leetcode.ex_571_number VALUES
('0' , '7' ),
('1' , '1' ),
('2' , '3' ),
('3' , '1' )
​
​
​