Multiple Sum with different conditions in MySQL

Today I was working on my last project that involves some statistics on data. I had a table like this:

sample table
]1 My table, with time and data fields.

I needed the daily, monthly and yearly sum of the value field. The simplest approach was to have three different queries to retrieve the needed values:

--day
SELECT SUM(value) 
FROM table 
WHERE DATE(time)=CURDATE();
-- month
SELECT SUM(value) 
FROM table 
WHERE MONTH(time)=MONTH(CURDATE()) AND YEAR(time)=YEAR(CURDATE());
-- year
SELECT SUM(value) 
FROM table 
WHERE YEAR(time)=YEAR(CURDATE());

But I wasn’t satisfied. I wanted to have all three values using only one query. So I searched for this issue and this is the resulting query:

SELECT 
  SUM(CASE WHEN DATE(time)=CURDATE() 
    THEN value 
    ELSE 0 end) AS value_day,
  SUM(CASE WHEN MONTH(time)=MONTH(CURDATE()) AND YEAR(time)=YEAR(CURDATE()) 
    THEN value 
    ELSE 0 end) AS value_month,
  SUM(CASE WHEN YEAR(time)=YEAR(CURDATE()) 
    THEN value 
    ELSE 0 end) AS value_year
FROM table

Using the CASE construct, we increment independently the three values so that each row that satisfies the condition gets summed up.

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