Question

这里有一个复杂的SQL问题。

我目前有一个SELECT语句，它匹配多个字段，如下所示。

SELECT field1, field2, field3, field4, field5
FROM table
WHERE field1 = 'variable 1'  
AND field2 = 'variable 2' 
AND field3 = 'variable 3' 
AND field4 = 'variable 4' 
AND field5 = 'variable 5'

我想修改语句，使其使用OR代替AND，以便选择与任何字段匹配的所有记录。

下一步是使用评分系统对结果进行排名。

If field 1 was matched then 1000 is added to the score
If field 2 was matched then 800 is added to the score
If field 3 was matched then 600 is added to the score
If field 4 was matched then 10 is added to the score
If field 5 was matched then 1 is added to the score

因此...

匹配1 - 如果field2和field 3匹配则分数为1400

匹配2 - 如果field1和field 4匹配则分数为1010

匹配1将位于结果的顶部。

任何帮助实现这一目标的SQL都会受到赞赏。

Answer 1

TRY：

SELECT
    ....
    FROM ....

    ORDER BY
        (CASE WHEN field1 = 'variable 1' THEN 1000 ELSE 0 END
        +CASE WHEN field2 = 'variable 2' THEN 800 ELSE 0 END
        +CASE WHEN field3 = 'variable 3' THEN 600 ELSE 0 END
        +CASE WHEN field4 = 'variable 4' THEN 10 ELSE 0 END
        +CASE WHEN field5 = 'variable 5' THEN 1 ELSE 0 END
        ) DESC

Answer 2

如果你需要在一个Select中做到这一点，那么它必须是一个可怕的东西：

SELECT field1, field2, field3, field4, field5
FROM table
WHERE field1 = 'variable 1'  
 OR field2 = 'variable 2' 
 OR field3 = 'variable 3' 
 OR field4 = 'variable 4' 
 OR field5 = 'variable 5'
ORDER BY (Case when field1 = 'variable 1' then 1000 else 0 end
        + Case when field2 = 'variable 2' then 800 else 0 end
        + Case when field3 = 'variable 3' then 600 else 0 end
        + Case when field4 = 'variable 4' then 10 else 0 end
        + Case when field5 = 'variable 5' then 1 else 0 end) DESC

编辑：如果要输出分数，还可以将多个案例部分作为输出字段放入SELECT中。然后，您可以通过引用其别名或其列索引（如Yannick M.在下面所做的那样）来订购

一个稍微好一点的解决方案可能是将其分解为多个查询，第一个将基本数据选择到临时表中，然后后续查询扫描临时表以调整分数值。但根据您的环境，这可能不是一种选择。

Answer 3

使用CASE表达式创建分数：

CASE WHEN field1 = 'variable 1' THEN 1000 ELSE 0 END +
CASE WHEN field2 = 'variable 2' THEN  800 ELSE 0 END +
...
AS score

然后你可以按分数排序（看看它，如果那是相关的）。或者，只需复杂表达式ORDER BY，就像在其他答案中一样。

Answer 4

这个怎么样：

SELECT field1, field2, field3, field4, field5
FROM table
WHERE field1 = 'variable 1'  
OR field2 = 'variable 2' 
OR field3 = 'variable 3' 
OR field4 = 'variable 4' 
OR field5 = 'variable 5'
ORDER BY
  CASE WHEN field1 = 'variable 1' THEN 1000 ELSE 0 END +
  CASE WHEN field2 = 'variable 2' THEN 800 ELSE 0 END +
  CASE WHEN field3 = 'variable 3' THEN 600 ELSE 0 END +
  CASE WHEN field4 = 'variable 4' THEN 10 ELSE 0 END +
  CASE WHEN field5 = 'variable 5' THEN 1 ELSE 0 END
DESC

Answer 5

SELECT field1, field2, field3, field4, field5,
  (CASE WHEN field1 = 'variable 1' THEN 1000 ELSE 0 END +
  CASE WHEN field2 = 'variable 2' THEN 800 ELSE 0 END +
  CASE WHEN field3 = 'variable 3' THEN 600 ELSE 0 END +
  CASE WHEN field4 = 'variable 4' THEN 10 ELSE 0 END +
  CASE WHEN field5 = 'variable 5' THEN 1 ELSE 0 END) as score
FROM table
ORDER BY 6 DESC;


+------+------+------+------+------+-------+
| f1   | f2   | f3   | f4   | f5   | score |
+------+------+------+------+------+-------+
|    1 |    2 | NULL | NULL | NULL |  1800 |
| NULL |    2 | NULL | NULL | NULL |   800 |
| NULL | NULL |    3 | NULL |    5 |   601 |
+------+------+------+------+------+-------+
3 rows in set (0.00 sec)

Answer 6

在我看来，最好的方法是在一个聚合查询中 - 如果它能回答你的问题。代码看起来像这样：

SELECT
    SUM(CASE WHEN FIELD1 = 'VARIABLE 1' THEN 1000 ELSE 0 END) F1FIND
,   SUM(CASE WHEN FIELD2 = 'VARIABLE 2' THEN 800 ELSE 0 END) F2FIND
,   SUM(CASE WHEN FIELD3 = 'VARIABLE 3' THEN 600 ELSE 0 END) F3FIND
,   SUM(CASE WHEN FIELD4 = 'VARIABLE 4' THEN 10 ELSE 0 END) F4FIND
,   SUM(CASE WHEN FIELD5 = 'VARIABLE 5' THEN 1 ELSE 0 END) F5FIND
FROM
    TABLE
;

如果你只是想为特定因子返回一个分数，你可以这样子查询：

SELECT
    F1FIND+F2FIND+F3FIND+F4FIND+F5FIND AS TOTAL_FIND
FROM
    ([ABOVE QUERY])
WHERE
    FACTOR = 'SOMETHING'
;

SQL顺序结果按匹配的字段数

6 个答案: