需求 ： tid ：帖子的id

　　　　sentence num：句子在帖子中的編號

　　　　wordindex：分好的每個詞 在帖子中的位置

　　　　channel ：這條帖子的關鍵詞

　　　　要求 計算word 在每一句中 與channel的詞距 ，若詞距絕對值小於三 則 word 和channel 標籤為關聯 若關聯數 /出現的總數>=2/3; 則此word和channel組成新詞，tip為1：

程式碼實現：

 1 DROP TABLE IF EXISTS temp_1;
 2 CREATE TEMP TABLE temp_1 AS
 3 SELECT 
 4  tid,
 5  sentence_num,
 
 6  wordindex,
 7  channel
 8 FROM "tmp10"
 9 WHERE 
10  word = channel  
11 LIMIT 100
12 ;
13 
14 SELECT
15  t1.*,
16  t2.*
17 FROM temp_1 t1
18 LEFT JOIN "tmp10" t2
19  on t2.tid= t1.tid
20  AND t2.sentence_num = t1.sentence_num
21 
22 
23 DROP TABLE IF EXISTS tmp_2;
24 CREATE TEMP table tmp_2 as
25 SELECT
 
26  t1.channel,
27  t1.wordindex as channel_index, 
28  t2.word,
29  t2.wordindex,
30  CASE 
31   WHEN (t1.wordindex::int - t2.wordindex::int) BETWEEN -3 AND 3 THEN 1 
32   ELSE 0
33  END AS dis
34 FROM temp_1 t1
35 LEFT JOIN "tmp10" t2
36  on t2.tid= t1.tid
37  AND t2.sentence_num = t1.sentence_num
38
 
 ;
39 
40 SELECT
41  channel,
42  word,
43  (COUNT(*) FILTER(WHERE dis = 1))::FLOAT/COUNT(*)
44 FROM tmp_2
45 GROUP BY
46  channel,
47  word