获取与重复值

Question

行我有以下表结构：

+----------+---------+ 
|  Trade  | 
+----------+---------+ 
| Trade_Id | Book_Id | 
+----------+---------+ 

+---------+-----------+ 
|  Book   | 
+---------+-----------+ 
| Book_Id | Book_Name | 
+---------+-----------+ 

+----------+--------------+---------------+ 
|     Keyword     | 
+----------+--------------+---------------+ 
| Trade_Id | Keyword_Name | Keyword_Value | 
+----------+--------------+---------------+ 

现在我想要从一个特定的书，有一个特定的重复关键字交易。我有一个查询工作，但我讨厌它，因为我基本上重复where子句中的wohle查询。

select 
    t.TRADE_ID, 
    kw.KEYWORD_VALUE 
from 
    trade t 
    inner join book b    on b.BOOK_ID = t.BOOK_ID 
             and b.BOOK_NAME = 'test123' 
    inner join TRADE_KEYWORD kw  on kw.TRADE_ID = t.TRADE_ID 
             and kw.KEYWORD_NAME = 'ISIN' 
where 
    kw.KEYWORD_VALUE in (
     select 
      kw2.KEYWORD_VALUE 
     from 
      trade t2 
      inner join book b2    on b2.BOOK_ID = t2.BOOK_ID 
               and b2.BOOK_NAME = 'test123' 
      inner join TRADE_KEYWORD kw2 on kw2.TRADE_ID = t2.TRADE_ID 
               and kw2.KEYWORD_NAME = 'ISIN' 
     group by kw2.KEYWORD_VALUE 
     having count (*) > 1) 

如何更优雅地做到这一点？ 谢谢！

Answer 1

select TRADE_ID, KEYWORD_VALUE from 
    (select 
     t.TRADE_ID, 
     kw.KEYWORD_VALUE, 
     count(kw.KEYWORD_VALUE) over(partition by kw.KEYWORD_VALUE) n 
    from 
     trade t 
     inner join book b    on b.BOOK_ID = t.BOOK_ID 
              and b.BOOK_NAME = 'test123' 
     inner join TRADE_KEYWORD kw  on kw.TRADE_ID = t.TRADE_ID 
              and kw.KEYWORD_NAME = 'ISIN' 
    )        
where n > 1; 

您可以使用分析功能。它们与集合函数类似，但是为每行提供结果（PARTITION BY与GROUP BY类似）。