Home  >  Article  >  Database  >  我写的推荐系统。哈哈。表格什么的自己猜吧

我写的推荐系统。哈哈。表格什么的自己猜吧

WBOY
WBOYOriginal
2016-06-07 14:57:091391browse

我写的推荐系统。哈哈。表格什么的自己猜吧。 无 INSERT INTO recommend (SELECT ut.userid,it.itemid, NOW() FROM user_tag ut,item_tag it WHERE EXISTS( SELECT it.tagid FROM item_tag it WHERE it.tagid IN (SELECT ut.tagid FROM user_tag ut)))

我写的推荐系统。哈哈。表格什么的自己猜吧。
INSERT INTO recommend (

SELECT ut.userid,it.itemid, NOW() FROM user_tag ut,item_tag it WHERE 
EXISTS
( 

SELECT it.tagid FROM item_tag it WHERE it.tagid IN (SELECT ut.tagid FROM user_tag ut)

)

)
Statement:
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Previous article:批量执行动态SQL语句Next article:SQLITE3 TUTORIAL