sql - 使用 SQL 查询统计单词出现次数

Question

我有两张 table 。

表1:

ID   SENTENCE
1    The shoes are good shoes.
2    There is a tree.
3    This is nice, nice, nice!

表2:

ID   WORD
1    The
1    shoes
1    are
1    good
1    shoes
2    There
2    is
2    a
2    tree
3    This
3    is
3    nice
3    nice
3    nice

我需要统计表1中每个句子中每个单词的出现次数。如果任何单词出现多次 (>1)，则计算它，否则跳过它。最后生成的表格应如下所示:

ID   SENTENCE                   CNT
1    The shoes are good shoes.  2
2    There is a tree.
3    This is nice, nice, nice!  3

Answer 1

您可以使用count() over():

select distinct t1.id,
  t1.sentence,
  coalesce(t2.cnt, 0) cnt
from table1 t1
left join 
(
  select t1.id, 
    t1.sentence,
    t2.word,
    count(t2.word) over(partition by t1.id, t2.word) cnt
  from table1 t1
  left join table2 t2
    on t1.id = t2.id
) t2
  on t1.id = t2.id
  and t2.cnt > 1
order by t1.id

参见SQL Fiddle with Demo .

或者您可以只使用count():

select t1.id,
  t1.sentence,
  coalesce(t2.cnt, 0) cnt
from table1 t1
left join 
(
  select t1.id, 
    t1.sentence,
    t2.word,
    count(t2.word) cnt
  from table1 t1
  left join table2 t2
    on t1.id = t2.id
  group by t1.id, t1.sentence, t2.word
  having count(t2.word) > 1
) t2
  on t1.id = t2.id
order by t1.id 

参见SQL Fiddle with Demo