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SQL for summing only new values

开发者 https://www.devze.com 2023-01-07 03:03 出处:网络
i have a table like this NAMEVALUE ----------------- bla1 bla2 bla2 bla3 bla1 bla4 bla2 How can i do a sumof ONLY different values , and ignore the repeating values (is it possible?)?

i have a table like this

NAME    VALUE
-----------------
bla      1
bla      2
bla      2
bla      3
bla      1
bla      4
bla      2

How can i do a sum of ONLY different values , and ignore the repeating values (is it possible?)? Something like this :

 SELECT SUM(??condition?? value) as total FROM table
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And the sum should be 10.

Thank you!


Wouldn't

SELECT SUM(DISTINCT value) FROM mytable;

do the trick?


This should work:

SELECT SUM(value) as total FROM (SELECT DISTINCT value FROM table) tmp;

Source: http://forums.mysql.com/read.php?97,203188,203787#msg-203787

SELECT SUM(DISTINCT value) as total FROM table

Source: http://dev.mysql.com/doc/refman/5.1/en/group-by-functions.html#function_sum

The second solution is better because it does not create temporary table. Therefore it is faster.


If you want to sum all distinct values then you can use DISTINCT:

SELECT SUM(DISTINCT value) AS total FROM yourtable

If you want to calculate a different sum for each name then add GROUP BY:

SELECT name, SUM(DISTINCT value) AS total 
FROM yourtable
GROUP BY name

Or to only consider a specific name:

SELECT SUM(DISTINCT value) AS total 
FROM yourtable
WHERE name = 'bla'
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