There are two tables (only used to represent structures)
name code
1 --------1
1 --------2
1 --------3
2----------5
2----------4
2.
code num
1------ -2
2 ------ 3
3------ 4
4-------5
5--------6
I want to get data like name-----sum(num)
Please give me some advice
3
0
0
select name,sum(num) from A inner join B on A.code =B.code group by name
SELECT SUM(num) FROM 2 WHERE code IN (SELECT code FROM 1 WHERE name = 1)
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