避免多个`或`表达式

我有以下oracle SQL及其工作原理，但与所有ors 比较难看。有更简洁的方法吗？

SELECT * FROM foobar WHERE
  (SUBJECT ='STAT' and TERM ='111') or  
  (SUBJECT ='STAT' and TERM ='222') or  
  (SUBJECT ='ENGLISH' and TERM ='555') or 
  (SUBJECT ='COMM' and TERM ='444') or
  (SUBJECT ='COMM' and TERM ='333') or  
  (SUBJECT ='STAT' and TERM ='666')
  ...

oracle query-refactor

— 凯尔·德科特（Kyle Decot）
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Answers:

您可能更喜欢这样的事情：

select *
from foobar
where (subject,term) in ( ('STAT','111')
                         ,('STAT','222')
                         ,('ENGLISH','555')
                         ,('COMM','444')
                         ,('COMM','333')
                         ,('STAT','222')
                         ,('STAT','666') 
                        );

DBFiddle 在这里

— 杰克说尝试topanswers.xyz
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我希望MS SQL Server具有此语法。

— Ross Presser 2015年

@RossPresser我认为要添加语法有一个Connect项目/建议。您可以投票;）

— ypercubeᵀᴹ17年

我发现，是一些大致为能够：

SELECT * FROM foobar INNER JOIN (SELECT * FROM (VALUES ('4','a'),('5','b')) AS myTable(subject,term)) ON myTable.subject=foobar.table and mytable.term=foobar.term

— 罗斯压

但是我想要这个实际的语法。知道Connect项目在哪里吗？

— 罗斯·普泽德

@RossPresser在这里是：添加对ANSI标准行值构造函数的支持 MS的回答是：“您好。谢谢您的反馈。我们肯定会在将来的SQL Server版本中考虑行值构造函数。” 至少10年后，此请求仍未解决。

— ypercubeᵀᴹ

就纯代码清洗而言，以下代码看起来更干净：

SELECT * 
  FROM foobar 
  WHERE (SUBJECT = 'STAT' and TERM IN ('111','222','666') )
    OR  (SUBJECT = 'COMM' and TERM IN ('333','444') )
    OR  (SUBJECT = 'ENGLISH' and TERM = '555' ) ;

根据应用程序和逻辑的重用频率，可能值得设置查找表以应用逻辑：

CREATE TABLE foobar_lookup (SUBJECT VARCHAR2(7), TERM VARCHAR2(3)) ;

INSERT INTO foobar_lookup SELECT 'STAT',    '111' FROM dual ;
INSERT INTO foobar_lookup SELECT 'STAT',    '222' FROM dual ;
INSERT INTO foobar_lookup SELECT 'STAT',    '666' FROM dual ;
INSERT INTO foobar_lookup SELECT 'COMM',    '444' FROM dual ;
INSERT INTO foobar_lookup SELECT 'COMM',    '333' FROM dual ;
INSERT INTO foobar_lookup SELECT 'ENGLISH', '555' FROM dual ;

SELECT f.* FROM foobar f
JOIN foobar_lookup fl 
    ON fl.subject = f.subject
    AND fl.term = f.term ;

— 托马斯·克莱伯格
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这是另一种方法。使用where（col1，col2）可能会导致Oracle不使用任何索引，但这看起来像查询表，因此可能会更好。一旦测试了各种版本，您就会知道。

  WITH subject_terms 
            (subject,   term) AS
    ( SELECT 'STAT'   , '111' FROM dual UNION ALL
      SELECT 'STAT'   , '222' FROM dual UNION ALL
      SELECT 'ENGLISH', '555' FROM dual UNION ALL
      SELECT 'COMM'   , '444' FROM dual UNION ALL
      SELECT 'COMM'   , '333' FROM dual UNION ALL
      SELECT 'STAT'   , '666' FROM dual )
SELECT * 
  FROM foobar             fb
 INNER JOIN subject_terms st
    ON fb.subject = st.subject
   AND fb.term    = st.term;

DBFiddle 在这里

— 甘道夫989
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