The code example from this page shows how to make a MySQL SELECT with JOIN table of different database, using PDO.
The trick is to specify both the database name and table in the SQL query, by using the syntax: database_name.table_name.
- This method works if you use an user and password for connecting to MySQL that has access to both databases.

Complete code example

// Data for connecting to MySQL
$mysql =['host'=>'localhost', 'dbname'=>'db_1', 'user'=>'root', 'pass'=>'password'];

//connects with PDO 
try {
  $conn = new PDO('mysql:host='. $mysql['host'] .'; dbname='. $mysql['dbname'], $mysql['user'], $mysql['pass']);
  $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); //set the PDO error mode to exception
}
catch(PDOException $e){ exit('Connection failed: '. $e->getMessage());}

$sql ="SELECT t1.id, t1.name, t2.col_db2 FROM db_1.table1 AS t1
 LEFT JOIN db_2.table2 AS t2 ON t1.id = t2.id";
$stmt = $conn->query($sql);

if($stmt !== false) {
  //shows selected data
  foreach($stmt as $row) {
    echo $row['id'] .'--'. $row['name'] .'--'. $row['col_db2'] .'<br>';
  }
}
else {
  echo '0 results';
}
- In this way you can join multiple tables from different databases.

Daily Test with Code Example

HTML
CSS
JavaScript
PHP-MySQL
Which tag is used to add lists into <ul> and <ol> elements?
<dt> <dd> <li>
<ul>
 <li>http://coursesweb.net/html/</li>
 <li>http://coursesweb.net/css/</li>
</ul>
Which value of the "display" property creates a block box for the content and ads a bullet marker?
block list-item inline-block
.some_class {
  display: list-item;
}
Which instruction converts a JavaScript object into a JSON string.
JSON.parse() JSON.stringify eval()
var obj = {
 "courses": ["php", "javascript", "ajax"]
};
var jsonstr = JSON.stringify(obj);
alert(jsonstr);    // {"courses":["php","javascript","ajax"]}
Indicate the PHP class used to work with HTML and XML content in PHP.
stdClass PDO DOMDocument
$strhtml = '<body><div id="dv1">CoursesWeb.net</div></body>';
$dochtml = new DOMDocument();
$dochtml->loadHTML($strhtml);
$elm = $dochtml->getElementById("dv1");
echo $elm->nodeValue;    // CoursesWeb.net
Mysql SELECT JOIN tables on two different Databases

Last accessed pages

  1. Create simple Website with PHP (15240)
  2. Transparent Background, but not the text-content on it (1227)
  3. Ajax-PHP Chat Script (32266)
  4. Drag Racer V3 (15436)
  5. Insert, Select and Update NULL value in MySQL (17154)

Popular pages this month

  1. Qwop (7896)
  2. Drag Racer V3 (5541)
  3. Bubbles3 (2160)
  4. List with All the Games (1834)
  5. Flash Games - Free online Games (1718)