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如何使MYSQL查询结果ORDER BY条件顺序?

[英]How to make MYSQL query results ORDER BY conditions order?

我的查询字符串如下:

SELECT ... FROM maintable
LEFT JOIN table1 on (maintable.id = table1.idx)
LEFT JOIN table2 on (table1.idy = table2.idy)
LEFT JOIN table3 on (table2.idz = table3.idz)
WHERE (condition1 OR condition2 OR condition3)
AND maintable.status = static

//condition1 & condition2 & condition3 are kind of
table3.idz = 101, table3.idz = 3, maintable.id IN (1,2,3,4), and so on

对于结果,我想,以满足项目condition1首先被退回,则符合项condition2 ,最后符合项condition3 有任何想法吗?

要按所需顺序进行排序,请在ORDER BY中使用条件,但在它们之后使用DESC

SELECT *
FROM person
WHERE (condition1 OR condition2 OR condition3)
AND maintable.status = static
ORDER BY
    condition1 DESC,
    condition2 DESC,
    condition3 DESC

如果这不起作用,因为您的查询更复杂,那么您可以使用布尔逻辑将您的查询(A OR B OR C) AND D更改为(A AND D) OR (B AND D) OR (C AND D)那么你可以使用以下查询:

SELECT *
FROM person
WHERE (condition1 OR condition2 OR condition3)
AND maintable.status = static
ORDER BY
    condition1 AND static DESC,
    condition2 AND static DESC,
    condition3 AND static DESC

这里不需要AND static ,因为所有行都返回它,但是在一个更复杂的例子中(你也返回一些非静态的行),你必须以这种方式去做。

这应该工作:

ORDER BY condition1, condition2, condition3

例如

ORDER BY (weight > 500), (height > 3), (height < 2)

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