MySQL calculate ratios from group-by query result - mysql

Question

ADD:
SQL query:
SELECT s.name
, d.feeling
, COUNT(1) AS times
FROM data_table d
, staff s
WHERE d.nid = s.id
AND d.project_id = 1
AND d.crawl_time BETWEEN '2018-10-17' AND '2018-10-24'
AND LENGTH(TRIM(d.feeling)) > 0
GROUP
BY d.nid
, d.feeling
ADD (END)
I write a sql to query the times of each body's feelings group by name and feeling. Here is the result.
-- a certain sql returns, not an existing table --
`name` `feeling` `times` (expect)
Jack happy 10 0.45
Jack sad 7 0.31
Jack common 5 0.22
Lily happy 3 0.27
Lily sad 6 0.54
Lily common 2 0.18
Sam happy 6 0.42
Sam sad 7 0.5
Sam common 1 0.07
Now the aim is to calculate the ratio of everyone's feelings. For example, the happy feeling of Jack takes 10/(10+7+5) of his feelings, and for sad feeling is 7/(10+7+5).
When using SUM(result.count) and GROUP BY name to figure, the sad or common feelings cannot show. Then I use subquery, but the table does not exist. Is there anyway to work without creating a view?

Answer 1

One solution which should work on any version of MySQL uses a subquery to find the sum of times for each name, and then joins to it:
SELECT
t1.name,
t1.feeling,
t1.times,
t1.times / t2.times_sum AS feeling_ratio
FROM yourTable t1
INNER JOIN
(
SELECT name, SUM(times) AS times_sum
FROM yourTable
GROUP BY name
) t2
ON t1.name = t2.name;
If you are using MySQL 8+ or later, and have access to analytic functions, then there is simpler way of writing this:
SELECT
t1.name,
t1.feeling,
t1.times,
t1.times / SUM(t1.times) OVER (PARTITION BY t1.name) AS feeling_ratio
FROM yourTable t1;