Usando wpdb para conectarse a una base de datos separada

Sí,esposible.

El objeto wpdb sepuede utilizarpara acceder a cualquierbase de datos y consultar cualquiertabla.Absolutamenteno haynecesidad deestar relacionado con Wordpress,lo cualesmuyinteresante.

Elbeneficioes la capacidad de usartodas las clases yfunciones de wpdb como get_results,etc.para queno seanecesario reinventar la rueda.

He aquí cómo:

 $mydb = new wpdb('username','password','database','localhost');
$rows = $mydb->get_results("select Name from my_table");
echo "<ul>";
foreach ($rows as $obj) :
   echo "<li>".$obj->Name."</li>";
endforeach;
echo "</ul>";
 

Yes it's possible.

The wpdb object can be used to access any database and query any table. Absolutely no need to be Wordpress related, which is very interesting.

The benefit is the ability to use all the wpdb classes and functions like get_results, etc so that there's no need to re-invent the wheel.

Here's how:

$mydb = new wpdb('username','password','database','localhost');
$rows = $mydb->get_results("select Name from my_table");
echo "<ul>";
foreach ($rows as $obj) :
   echo "<li>".$obj->Name."</li>";
endforeach;
echo "</ul>";

Conectarse a una segundabase de datosesfácilen WordPress,simplemente crea unanuevainstancia de la clase WPDB y úsela de lamismamanera que usaría lainstanciaestándar $ wpdb quetodos conocemos y amamos.

Suponiendo que la segundabase de datostiene lamismainformación deinicio de sesión que laprincipal de WP,inclusopuede usar las constantespredefinidas de wp-config.phpparaevitar codificar lainformación deinicio de sesión.

 /**
 * Instantiate the wpdb class to connect to your second database, $database_name
 */
$second_db = new wpdb(DB_USER, DB_PASSWORD, $database_name, DB_HOST);
/**
 * Use the new database object just like you would use $wpdb
 */
$results = $second_db->get_results($your_query);
 

Connecting to a second database is easy in WordPress, you simply create a new instance of the WPDB class and use it the same way you would use the standard $wpdb instance we all know and love.

Assuming the second database has the same login information as the main WP one you can even use the predefined constants from wp-config.php to avoid hardcoding the login information.

/**
 * Instantiate the wpdb class to connect to your second database, $database_name
 */
$second_db = new wpdb(DB_USER, DB_PASSWORD, $database_name, DB_HOST);
/**
 * Use the new database object just like you would use $wpdb
 */
$results = $second_db->get_results($your_query);

Nadie ha dichoesto,así quepenséen agregar unaforma aúnmásfácil ..

siempre que subase de datos adicionaltenga losmismos detalles de usuario/contraseñapara acceder aella que subase de datos de wordpress,puede usarelnombre de labase de datos antes delnombre de latabla comoeste

 $query = $wpdb->prepare('SELECT * FROM dbname.dbtable WHERE 1');
$result = $wpdb->get_results($query);
 

no one has said this so I thought I'd add an even easier way..

as long as your additional database has the same user/pass details to access it as your wordpress database you can use the database name before the table name like this

$query = $wpdb->prepare('SELECT * FROM dbname.dbtable WHERE 1');
$result = $wpdb->get_results($query);

Sibien estosfuncionarán,perderá la capacidad de usar las "otras"funcionespersonalizadas,comoget_post_custom y consultas de wordpress.La solución simplees

 $wpdb->select('database_name');
 

que cambia labase de datosen todoel sistema (unmysql select_db).Elmétodo database.tablefunciona si solo desea realizar una consulta simple,pero si desea acceder a otroblog de wordpress,puede usar select.Solotendrá que volver a cambiarlo cuando hayaterminado o sublogpuede hacer cosasextrañas.

While these will work, you'll lose the ability to use the "other" custom features such as get_post_custom and wordpress queries. The simple solution is

$wpdb->select('database_name');

which changes the database system-wide (a mysql select_db). The database.table method works if you just want to make a simple query, but if you want to access another wordpress blog you can use select. You'll just need to change it back when you're done or your blog may do strange things.

Todavíanopuedo comentar,pero quería ampliar la respuesta de Wadih M. (queesgenial).

La clase debase de datos de WPes una versiónpersonalizada delezSQL de Justin Vincent.Si legusta lainterfaz y desea crear un sitio quenoestébasadoen WordPress,esposible que desee comprobarlo: http://justinvincent.com/ezsql

I can't comment yet, but I wanted to expand on Wadih M.'s answer (which is great).

WP's database class is a customized version of Justin Vincent's ezSQL. If you like the interface and you're wanting to do a site that's not WordPress-based, you might want to check it out: http://justinvincent.com/ezsql

Teníaproblemaspara usar $wpdbpara conectarme a una segundabase de datos deblogs desde un sitioprincipal quenecesita actualizar dosblogs.Usé $wpdb->select($dbname, $dbh)para seleccionar la segundabase de datos,perotodavía obtenía resultados de laprimerabase de datos.

Resolvíelproblema llamando a wp_cache_flush()paraborrar la caché de WordPress antes de llamar a lasfunciones de WPen la segundabase de datos.

I was struggling with using $wpdb to connect to a second blog database from a parent site that needs to update two blogs. I used $wpdb->select($dbname, $dbh) to select the second database, but I was still getting results from the first database.

I resolved the problem by calling wp_cache_flush() to clear the WordPress cache before calling WP functions on the second database.