Getting column value when SQL query has aliases

问题

I have a SQL query that has alias in it. The problem is, when I try to get the values of columns it doesn't show the correct values:

$sql = "SELECT p.ID, p.ProfileID, p.ModuleID, p.View, p.Add, p.Edit, p.Delete, m.Name, m.ID FROM permission AS p, module AS m WHERE p.ModuleID = m.ID ORDER BY p.ProfileID ASC, m.Name ASC";

    $result = array();
    $i = 0;
    foreach ($this->dbconnect->query($sql) as $row)
    {
        $result[$i] = array(
        'ID' => $row['p.ID'],
        'ProfileID' => $row['p.ProfileID'],
        'ModuleID' => $row['p.ModuleID'],
        'View' => $row['p.View'],
        'Add' => $row['p.Add'],
        'Edit' => $row['p.Edit'],
        'Delete' => $row['p.Delete']);

        $i += 1;
    }

Running shows no value when in the database it's actually 10.

If I change the above code to the following:

$sql = "SELECT p.ID, p.ProfileID, p.ModuleID, p.View, p.Add, p.Edit, p.Delete, m.Name, m.ID FROM permission AS p, module AS m WHERE p.ModuleID = m.ID ORDER BY p.ProfileID ASC, m.Name ASC";

    $result = array();
    $i = 0;
    foreach ($this->dbconnect->query($sql) as $row)
    {
        $result[$i] = array(
        'ID' => $row['ID'],
        'ProfileID' => $row['ProfileID'],
        'ModuleID' => $row['ModuleID'],
        'View' => $row['View'],
        'Add' => $row['Add'],
        'Edit' => $row['Edit'],
        'Delete' => $row['Delete']);

        $i += 1;
    }

Miraculously, running shows the value of m.ID instead of p.ID. It is strange why the first example is incorrect. Am I missing something here?

回答1:

Use aliases in SELECT to each column, which are same:

$sql = "SELECT p.ID AS permission_id, p.ProfileID, p.ModuleID, p.View, p.Add, p.Edit, p.Delete, m.Name, m.ID AS module_id FROM permission AS p, module AS m WHERE p.ModuleID = m.ID ORDER BY p.ProfileID ASC, m.Name ASC";

then:

foreach(...)
{
    $result[$i] = array(
    'Perm_ID' => $row['permission_id'],
    'Module_ID' => $row['module_id'],
    ...
}

回答2:

You should something like this...

SELECT p.ID as p_ID, ...

And

'ID' => $row['p_ID'],

来源：https://stackoverflow.com/questions/18932205/getting-column-value-when-sql-query-has-aliases

标签

php

mysql

pdo

alias