Thinkphp的关联查询

文章表：article (字段：id  category_id  title  content)；

类别表：category (字段：id name)；

关联查询语句：

1.table();

$res = M('Article')->table('article as a,category as c')->where('a.id=1 AND a.category_id = c.id')->field('a.id,a.title,a.content,c.name as category_name')->find();

2.join();

$row = M('Article')->alias('a')
        ->join('category AS c ON a.category_id = c.id')
        ->field('a.id,a.title,a.content,c.name as category_name')
        ->where(array('a.id' => 1))

        ->find();

3.原生查询

$Model = new Model(); 

$sql = 'SELECT a.id,a.title,a.content,c.name as category_name FROM article as a,category as c where a.id=1 AND a.category_id=c.id'

$res = $Model->query($sql);