CodeIgniter / PHP / MySQL：使用JOIN检索数据 [英] CodeIgniter/PHP/MySQL: Retrieving data with JOIN

问题描述

我是新的PHP / MySQL和超级新的CodeIgniter ..
我有许多MySQL表中的信息。我想用JOIN检索它的表主键等于$变量...我如何做，并获得所有的字段没有主键字段

I'm new to PHP/MySQL and super-new to CodeIgniter.. I have information in many MySQL tables. I want to retrieve it with JOIN where the tables primary keys are equal to $variable... How can I do it and get all the fields without the primary key field???

我现在做的是这个（只有两个表加入这里）：

What I'm doing now is this (only two tables joined here):

function getAll($id) {

    $this->db->select('*');
    $this->db->from('movies');
    $this->db->join('posters', 'movies.id= posters.id');
    // WHERE id = $id ... goes here somehow...
    $q = $this->db->get();

    if ($q->num_rows() == 1) {
        $row = $q->row();
        $data = array(
                'id' => $row->id,
                'title' => $row->title,
                'year' => $row->year,
                'runtime' => $row->runtime,
                'plotoutline' => $row->plotoutline,
                'poster_url' => $row->poster_url
            );
    }

    $q->free_result();
    return $data;

id（PK），title，year，runtime和plotoutline是第一个表格的列，poster_url是来自第二个表的字段。

id (PK), title, year, runtime and plotoutline are columns from the first table and poster_url is a field from the second table. The second table also contains an ID (PK) column that I don't want to Retrieve because I already have.

推荐答案

Jon在第二个表格中包含了一个ID是对的。这里有一个例子：

Jon is right. Here's an example:

$this->db->select('movies.id, 
                   movies.title, 
                   movies.year, 
                   movies.runtime as totaltime,  
                   posters.poster_url');
$this->db->from('movies');
$this->db->join('posters', 'movies.id= posters.id');
$this->db->where('movies.id', $id);
$q = $this->db->get();

这将返回具有 - > id， - > title， - > year， - > totaltime ，和 - > poster_url属性。

This will return objects that have ->id, ->title, ->year, ->totaltime, and ->poster_url properties. You won't need the additional code to fetch the data from each row.

不要忘记，如果Active Record语法有点笨拙，您可以使用完整的SQL查询并获得相同的结果：

Don't forget, if the Active Record syntax gets a little unwieldy, you can use full SQL queries and get the same results:

$sql = "SELECT movies.id,
        movies.title,
        movies.year,
        movies.runtime as totaltime,
        posters.poster_url
        FROM movies
        INNER JOIN posters ON movies.id = posters.id
        WHERE movies.id = ?"

return $this->db->query($sql, array($id))->result();

这两种表单都会确保您的数据正确转义。

Both forms will ensure that your data is escaped properly.

CodeIgniter Active Record

CodeIgniter中的查询绑定

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