Question

我有一个类似SELECT * FROM my_table WHERE column_a = 'foo' OR column_b = 'foo' ORDER BY column_c;的查询。

是否有办法在结果中首先获得与第一个条件column_a = 'foo'匹配的行（由column_c值排序），然后匹配第二个条件column_b = 'foo'的行（按顺序排列） column_c值）？

Answer 1

您可以通过布尔表达式对行进行排序，例如：

SELECT * 
FROM my_table 
WHERE column_a = 'foo' OR column_b = 'foo' 
ORDER BY column_a <> 'foo', column_b <> 'foo', column_c;

Answer 2

SELECT * 
FROM my_table 
WHERE column_a = 'foo' OR column_b = 'foo'
ORDER BY CASE WHEN column_a = 'foo' then 1 ELSE 2 END, column_c

同样，如果你有另一个OR条件：

SELECT * 
FROM my_table 
WHERE column_a = 'foo' OR column_b = 'foo' OR column_c = 'foo'
ORDER BY CASE WHEN column_a = 'foo' then 1 WHEN column_b = 'foo' then 2 ELSE 3 END, column_d

Answer 3

您可以添加order by column_a, column_b, column_c，这将订购行

根据匹配条件排序SQL查询结果

3 个答案: