INNER JOIN在计算单词出现的同一桌子上

Question

http://sqlfiddle.com/#!2/e6382

id   id_news  word
 1    6       superman
 2    6       movie
 3    6       review
 4    6       excellent
 5    7       review
 6    7       guardians of the galaxy
 7    7       great
 8    8       review
 9    8       superman
10    8       movie
11    8       great

我有一个小问题,我试图通过具有阈值设置的单词来处理不同的新闻,在提供的示例中id_news 6应该与之相关8但不是7因为7只有2单词有共同之处我只想检测那些至少有3单词的人共同的.

Answer 1

尝试这个自加入：

SELECT
  wa1.id_news id_news_1,
  wa2.id_news id_news_2,
  count(wa2.word) cnt_words
FROM word_analysis wa1
INNER JOIN word_analysis wa2
ON wa1.id_news <> wa2.id_news AND wa1.word = wa2.word
GROUP BY wa1.id_news, wa2.id_news
HAVING count(wa2.word) >= 3
ORDER BY wa1.id_news, wa2.id_news;

SQL Fiddle demo