按最大条件匹配排序 [英] Order by Maximum condition match

问题描述

请帮助我创建一个包含10个"where"子句的选择查询，其顺序应如下所示: 结果应按大多数关键字(条件)匹配到不匹配的顺序显示.

Please help me to create a select query which contains 10 'where' clause and the order should be like that: the results should be displayed in order of most keywords(where conditions) matched down to least matched.

注意:所有10个条件都带有或".

NOTE: all 10 condition are with "OR".

请帮助我创建此查询. 我正在使用ms-sql server 2005

Please help me to create this query. i am using ms-sql server 2005

赞:

Select *
  from employee
 where empid in (1,2,4,332,434)
    or empname like 'raj%'
    or city = 'jodhpur'
    or salary >5000

在上面的查询中，所有与最大条件匹配的记录都应位于顶部，而较少匹配条件的记录应位于底部.

In above query all those record which matches maximum conditions should be on top and less matching condition record should be at bottom.

推荐答案

SELECT *
  FROM (SELECT (CASE WHEN cond1 THEN 1 ELSE 0 END +
                CASE WHEN cond2 THEN 1 ELSE 0 END +
                CASE WHEN cond2 THEN 1 ELSE 0 END +
                ...
                CASE WHEN cond10 THEN 1 ELSE 0 END
               ) AS numMatches,
               other_columns...
          FROM mytable
       ) xxx
 WHERE numMatches > 0
 ORDER BY numMatches DESC

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