Question

我需要从我的mysql表中选择一行。

在表中有两行，其中一个值相等。

TABLE
-----
articleId
keywordId

现在我需要选择一篇文章，其关键字ID = 1，以及关键字ID = 12。

关键字的每个链接都有自己的记录。

如果有一篇文章，如何匹配这两个关键字，我该怎么做一个选择查询？

Answer 1

试试这个：

SELECT *  
FROM tablename 
WHERE keywordId IN (1, 12) 
GROUP BY articleId 
HAVING COUNT(*) = 2;

检查SQL FIDDLE DEMO

Answer 2

这称为Relation Division。这是一种方法：

SELECT * 
FROM tablename 
WHERE articleId IN
(
   SELECT articleId
   FROM tablename
   WHERE KeywordId IN (1, 2) 
   GROUP BY articleId
   HAVING COUNT(KeywordId ) = 2
);;

Answer 3

SELECT * 
FROM `table_name` 
WHERE `keywordId` = '1' AND `keywordId` = '12'

Answer 4

您还可以为每个关键字使用子查询并加入

select k1.articleId from
(
    select articleId from TABLE where keywordId = 1
) k1
inner join
(
    select articleId from TABLE where keywordId = 12
) k2 on k1.articleId = k2.articleId

根据索引和表大小，这可能比Group By

更有效

Answer 5

select ArticleId from Table where keywordId = 1
Intersect
select ArticleId from Table where KeywordId = 12

Answer 6

SELECT * 
FROM table 
WHERE keywordId IN (1, 12);

MYSQL选择两个值一列

6 个答案: