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如何从数据库中选择不同的列,每个列给出另一个查询结果的和(或类似的)?

mysql php

Starx · 技术社区 · 14 年前

这是查询示例

SELECT 
    name, 
    sum(SELECT id FROM mytable WHERE cond='1' and cond2='2') as mysum1, 
    sum(SELECT id FROM mytable WHERE cond3='3' and cond4='4') as mysql2 
FROM 
    mytable 
WHERE 
    userid='1' and status='1';

显然这不起作用,但我想你现在可以理解我的意思了。如何以这种方式检索记录。

3 回复 | 直到 14 年前

MÄris KiseÄ¼ovs 14 年前

您需要计算子查询中的和:

SELECT 
    name, 
    (SELECT sum(numbers) FROM mytable WHERE cond='1' and cond2='2') as mysum1, 
    (SELECT sum(numbers) FROM mytable WHERE cond3='3' and cond4='4') as mysym2
FROM 
    mytable 
WHERE 
    userid='1' and status='1';

Gunjan 14 年前

试试这个

SELECT 
    name, 
    (SELECT SUM(id) FROM mytable WHERE cond='1' and cond2='2') as mysum1, 
    (SELECT SUM(id) FROM mytable WHERE cond3='3' and cond4='4') as mysql2 
FROM 
    mytable 
WHERE 
    userid='1' and status='1';

Naktibalda 14 年前

如果要获取与这些条件匹配的行数,请使用此查询:

SELECT 
    name, 
    SUM(cond='1' AND cond2='2') AS mysum1,
    SUM(cond3='3' AND cond4='4') AS mysum2
FROM mytable 
WHERE 
    userid='1' AND 
    status='1';

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