Viene visualizzato l’avviso “Errore nello stabilire una connessione al database” in WordPress?
Si tratta di un errore fatale che rende il sito inaccessibile agli utenti. Si verifica quando WordPress non è in grado di stabilire una connessione al database. Poiché diversi fattori possono influire su questa connessione, l’errore può essere un po’ difficile da risolvere per i principianti.
In questo articolo vi mostreremo come risolvere facilmente l'”Errore nello stabilire una connessione al database” sul vostro sito WordPress, passo dopo passo.
Cosa causa l’errore di stabilire una connessione al database in WordPress?
Un database è un software che facilita l’archiviazione, l’organizzazione e il recupero di dati da altri software.
Come sistema di gestione dei contenuti, WordPress utilizza un database per memorizzare tutti i contenuti e gli altri dati del sito web. Si connette quindi al database ogni volta che qualcuno visita il vostro sito web.
WordPress ha bisogno delle seguenti informazioni per connettersi al database:
- Il nome del database
- Nome utente e password del database
- Server di database
Queste informazioni sono memorizzate nel file di configurazione di WordPress, chiamato wp-config.php.
Se una di queste informazioni non è corretta, WordPress non riuscirà a connettersi al server del database e verrà visualizzato l’errore “Errore nello stabilire una connessione al database”.
È uno degli errori più comuni di WordPress. Oltre alle credenziali errate, questo errore può comparire anche se il server del database è inattivo o i file del database sono corrotti.
Detto questo, vediamo come risolvere il problema “Errore nello stabilire la connessione al database” in WordPress con una risoluzione dei problemi passo dopo passo.
1. Controllare le credenziali del database di WordPress
Il motivo più comune per cui si verifica un errore di connessione al database è la presenza di credenziali errate. Se avete recentemente spostato il vostro sito WordPress su un nuovo host, è probabile che il problema sia questo.
Le credenziali del database di WordPress sono memorizzate nel file wp-config.php. È il file di configurazione di WordPress che contiene importanti impostazioni, tra cui le informazioni sul database.
Se non avete mai modificato un file wp-config.php, date un’occhiata alla nostra guida per principianti su come modificare il file wp-config.php per maggiori istruzioni.
Si cercheranno le seguenti righe nel file wp-config.php:
// ** MySQL settings - You can get this info from your web host ** //
/** The name of the database for WordPress */
define( 'DB_NAME', 'database_name_here' );
/** MySQL database username */
define( 'DB_USER', 'username_here' );
/** MySQL database password */
define( 'DB_PASSWORD', 'password_here' );
/** MySQL hostname */
define( 'DB_HOST', 'localhost' );
In questo caso, è necessario assicurarsi che le informazioni relative al nome del database, al nome utente, alla password e all’host del database siano corrette.
Potete confermare queste informazioni dalla dashboard del vostro account di hosting WordPress. Per questo tutorial utilizzeremo Bluehost, ma la procedura sarà simile anche per altri pannelli di hosting.
Una volta effettuato l’accesso, fare clic sulla scheda “Sito web” nella colonna di sinistra e poi passare alla scheda “Avanzate”. Quindi, scorrere fino alla sezione “Database” e fare clic sul pulsante “Gestisci” accanto ad essa.
In questo modo si aprirà la pagina dei database MySQL in cPanel in una nuova finestra.
Qui, nella sezione “Database corrente”, si trovano il nome del database e il nome utente. Ricordate di copiare e incollare questi dati in un blocco note per poterli aggiungere al file wp-config.
Quindi, scorrere fino alla sezione “Utenti attuali”, dove è possibile fare clic sul link “Cambia password” accanto al nome del database.
Si accede così a una nuova schermata, in cui è possibile modificare la password del database secondo le proprie esigenze.
Una volta confermati tutti i dettagli del database, è possibile modificare le informazioni nel file wp-config.php, se necessario.
Quindi, provare a visitare nuovamente il sito web per verificare se l’errore di connessione al database è scomparso.
Se l’errore è ancora presente, significa che c’è qualcos’altro che non va.
2. Controllare le informazioni sull’host del database
Se si è certi che il nome del database, il nome utente e la password siano corretti, occorre assicurarsi di utilizzare le informazioni corrette sull’host del database.
La maggior parte delle società di hosting WordPress utilizza localhost come host del database. Tuttavia, alcune società di hosting WordPress gestite utilizzano server separati per ospitare i database. In questo caso, le informazioni sull’host del database non saranno localhost.
Ciò significa che dovrete contattare la vostra società di hosting WordPress per confermare questi dettagli.
3. Riparazione del database di WordPress
Ora potreste ricevere un errore diverso nella dashboard di wp-admin, come “Una o più tabelle del database non sono disponibili” o “Potrebbe essere necessario riparare il database”. In questo caso, è necessario riparare il database.
È possibile farlo aggiungendo la seguente riga nel file wp-config.php. Assicuratevi di aggiungerla subito prima della riga “Questo è tutto, smettete di modificare! Buon blog”:
define('WP_ALLOW_REPAIR', true);
Una volta fatto ciò, è possibile vedere le impostazioni visitando questa pagina: http://www.yoursite.com/wp-admin/maint/repair.php. Assicuratevi di sostituire yoursite.com con il vostro nome di dominio.
A questo punto, è necessario fare clic sul pulsante “Ripara database” per avviare il processo.
Nota: non è necessario che l’utente sia connesso per accedere alla pagina di riparazione del database. Una volta terminata la riparazione e l’ottimizzazione del database, assicurarsi di rimuovere questa riga di codice dal file wp-config.php.
Tuttavia, se non volete aggiungere alcun codice al vostro sito, potete anche riparare il database dal pannello di controllo del vostro account di hosting.
Visitate il vostro account di hosting e aprite la pagina “Siti web” dalla colonna di sinistra. Quindi, passate alla scheda “Avanzate” e fate clic sul pulsante “Gestisci” nella sezione Database.
Si aprirà cPanel in una nuova scheda. Qui, scorrere fino alla sezione “Modifica database” e scegliere il nome del database dal menu a discesa “Ripara database”.
Una volta fatto ciò, è sufficiente fare clic sul pulsante “Ripara database” per avviare il processo.
Il pannello di hosting riparerà automaticamente il database.
Una volta completato il processo, verrà visualizzato un messaggio di successo.
Ora potete visitare il vostro sito WordPress per vedere se l’errore è stato risolto o meno.
4. Controllare se il server di database è inattivo
Se tutto sembra essere corretto e WordPress non riesce ancora a connettersi al database, è possibile che il server del database(server MySQL) sia inattivo.
Questo potrebbe accadere a causa del traffico intenso su un server. Il vostro server host non è in grado di gestire il carico (soprattutto se avete un hosting condiviso).
Per questo motivo, il vostro sito diventerà lento e potrebbe anche dare errore ad alcuni utenti. In questo caso, dovreste telefonare o chattare con il vostro provider di hosting e chiedere se il vostro server MySQL è reattivo.
Inoltre, se sullo stesso server sono in esecuzione altri siti web, è possibile selezionare questi siti per verificare che il server SQL sia giù.
Se non avete altri siti sullo stesso account di hosting, andate semplicemente nel vostro cruscotto di hosting e passate alla scheda “Avanzate”.
Successivamente, fare clic sul pulsante “Gestisci” accanto alla sezione phpMyAdmin.
Si aprirà phpMyAdmin in una nuova finestra, dove si dovrà fare clic sull’opzione “Database” in alto.
Quindi, fare clic sul nome del database per accedere alle sue impostazioni. Se ci riuscite, è il momento di verificare se l’utente del database ha i permessi sufficienti.
Per farlo, occorre creare un nuovo file chiamato testconnection.php e incollarvi il seguente codice:
<?php
$link = mysqli_connect('localhost', 'username', 'password');
if (!$link) {
die('Could not connect: ' . mysqli_error());
}
echo 'Connected successfully';
mysqli_close($link);
?>
Dopo aver incollato il codice, assicuratevi di sostituire il nome utente e la password con i vostri. Ora è possibile caricare questo file sul proprio sito web e accedervi tramite un browser.
Se lo script si è collegato correttamente, significa che l’utente dispone di permessi sufficienti e che l’errore è causato da qualcos’altro.
Ora è necessario tornare al file wp-config e analizzarlo per assicurarsi che tutti i dettagli siano accurati e senza errori di battitura.
Altre soluzioni che hanno funzionato per gli utenti
Se i suggerimenti per la risoluzione dei problemi di cui sopra non riescono a risolvere l’errore di connessione al database sul vostro sito web, potete provare questi ulteriori passaggi.
Come riportato dai nostri utenti, questi passaggi hanno aiutato alcuni di loro a risolvere l’errore di connessione al database sui loro siti web.
1. Aggiornare l’URL del sito WordPress
Potete provare ad aggiornare l’URL del sito WordPress utilizzando phpMyAdmin in cPanel.
È sufficiente accedere a phpMyAdmin dalla dashboard dell’account di hosting e selezionare il database di WordPress dall’elenco.
Quindi passate al menu SQL in alto e inserite la seguente query MySQL:
UPDATE wp_options SET option_value='YOUR_SITE_URL' WHERE option_name='siteurl'
L’aspetto dovrebbe essere il seguente:
Non dimenticate di fornire l’URL del vostro sito e di cambiare wp_options con il nome della vostra tabella, poiché potreste aver cambiato il prefisso della tabella di WordPress.
2. Riavvio del server Web
Gli utenti di server dedicati, server locali e server privati virtuali (VPS) possono provare a riavviare i loro server.
In questo modo si riavvia il server web e il database, che potrebbe risolvere alcuni problemi temporanei che causano l’errore.
3. Chiedere aiuto
Se tutto il resto non funziona, potrebbe essere necessario contattare la società di web hosting. Tutte le buone società di hosting WordPress vi aiuteranno a risolvere il problema, vi indicheranno la direzione giusta o addirittura lo risolveranno per voi.
Potete anche assumere sviluppatori WordPress utilizzando una piattaforma come WPBeginner Pro Services per aiutarvi a correggere questo problema a prezzi ragionevoli. Abbiamo un team dedicato di sviluppatori esperti di cui potete fidarvi per correggere qualsiasi problema di WordPress.
Inoltre, è possibile utilizzare il servizio per la manutenzione del sito, la riparazione di siti violati, l’ottimizzazione della velocità, la ricostruzione del sito web e l’ottimizzazione SEO.
Speriamo che questo articolo vi abbia aiutato a risolvere il problema “Errore nello stabilire una connessione al database” in WordPress. Potreste anche voler consultare la nostra guida alla risoluzione dei problemi di WordPress per avere suggerimenti su come risolvere i problemi di WordPress da soli, oppure la nostra selezione di esperti dei migliori strumenti per freelance e sviluppatori di WordPress.
Se questo articolo vi è piaciuto, iscrivetevi al nostro canale YouTube per le esercitazioni video su WordPress. Potete trovarci anche su Twitter e Facebook.
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Arafat says
Sometimes when I click on the “Publish” button to post a new article on my WordPress blog, then this error message appears:
“”Error establishing a database connection… This either means that the username and password information in your wp-config.php file is incorrect or we can’t contact the database server at localhost. This could mean your host’s database server is down…..””
Despite the error message appears, my post got published and there is no problem with visiting my site. This error does not come after each post publication. Sometimes it occurs. (My hosting reseller provider changed my server some days ago and this problem began after coming to the new server) What is the problem and how to solve it, please tell …… Thanks.
Editorial Staff says
It sounds like that you are having a memory issue on the new server.
Admin
Quinton says
The wp-config.php fix worked for me!! Thanks so much!
Josh says
I found a github repo which restarts the mysql server of wordpress if there is a database error using node.js http://goo.gl/gnXLR
Brian Deyo says
The quick snippet of PHP you provided was everything I needed to track down my issue.Thanks for the post!
Mario Ben says
I am very excited to find this solution. I got the exact problem with my website and after searching it, I found this amazing article.
Thank you so much!
HighHopes says
i was using Xampp on local machine to host my wordpress site and got error “Error Establishing the Database Connection”. first time i got that .. not sure why. i noticed in Xampp setup that the user and their privileges was deleted somehow. so i made a new user, using same user name as in ws-config, using host “localhost” and password same as in ws-config. worked like a charm
Olly says
You’re a lifesaver. Many thanks!
Karl says
I got error but after couple minutes everything got back normal, any way to avoid getting this error in future?
ben says
really great post !
helped me revive my wp-blog
thanks !
Demannu says
THANK YOU AUTHOR!!! Your little TestConnection script has saved me some serious non-paid time.
MUAH! / HUG / HIGH FIVE
El Hombre says
Really, this post has been a last-minute rescue. Many thanks to the editor.
Cheers el hombre
RaDLab says
Great article by the way.
My issue is somehow strange to me. In the last couple of days maybe weeks, every morning few of my sites on my server will get the Error establishing connection prompt. But after a few minutes, it starts to work without me doing anything. For example, I will get an email from a client that the Error is showing, but when I quickly check it on my end, it works fine, and The client will also notice it back up. So my problem is strange, I’m not sure what to check if everything seem to resolve itself. Is possible because of high traffic?
Editorial Staff says
Your issue is happening due to server overload. While this can mean high traffic, but it doesn’t always mean that. Sometimes, you have medium traffic but a bad plugin that is doing it. Other times, it is just high traffic.
Admin
RaDLab says
Thanks for the response.
This has never happened before. Just today, I’ve had to restart MySQL several times to keep many of my sites running, while I try to figure why it keeps losing connection. I’m really baffled by this. I’ve looked into the php.ini looking for where to increase any sort of limits, but I come up with nothing. It’s running right now, but soon it will fail to connect until I restart MySQL.
Any ideas on how to adjust to the high traffic and keep the MySQL server running?
Editorial Staff says
One thing you can do is increase your PHP memory limit. If you are running at 32MB, then that could be a reason. But you will get to a point when your current servers just can’t handle it. You would have to upgrade. Not sure what your server specs are, and how much load you are putting on it.
Run your server logs and see which processes are causing the load. Then see if those can be eliminated or optimized.
XeNNo says
I have seen that too myself.
This is happening to me, not only with wordpress but also with joomla and piwik and everything that i use to work with and needs a database.
My provider seems to have a different machine for the MySQL service and every now and then the connection between my sites and the MySQL server drops and give me failure.
You should check that this is your case too… and if so… get another host service
RaDLab says
Thanks for your input. I think I have narrowed it down to a db instance that was causing my MySQL to lose connection. It’s an instance running a ELGG system. Soon as I discovered how much load this instance was putting on the server, I deleted it. Since then, the Error has seem to have stopped. Who knew…
aly says
for me it was the sql password, which had a symbol ( ] ) at the end.
After giving up on all other “fixes,” I edited the password and presto! All good
yogesh says
a very big thanks from me to you because first i website show 500 internel error i fix it by read wpbeginner article now my site show error establishing a database connection i fix it by read your article….thankssssss
mhisyam6 says
My problem solved from this error just by reinstall/update the wordpress in the dashboard.
Raul says
Which version of wordpress did you upgrade to? I was previously on 3.5.1 but read that the 3.5 version is bugged, so I downgraded to 3.4.2. It’s more stable now but I still see the error…
Matt says
This has been a question asked by many of our past clients and is such a pain to explain this. Pretty much, 100% of the time I end up having to go in and fix it myself.
Fanto Chandra says
I just do repairing the database via cpanel-mysql database and choosing repair database and turn out working and can open the site again now. Thanks for the clue from your explanation.
Christine says
my own hosting company couldn’t help me. thank you. the first option worked great.
Alex Patterson says
Just went through this issue – and the problem turned out to be that my mysql database was by default using the old 16 byte hashes for the passwords, rather than the 41 byte hashes that the more recent versions of php scripts that WordPress uses requires.
To see if this is the issue, you can look at your user table in mysql:
select user, host, password from mysql.user;
If the password column for your user is 16 characters rather than 41, that is your issue.
You will need to temporarily set the hashing to 41 digits and then re-encode your password:
set @@session.old_passwords = 0;
set password for ‘wordpress_user’@’localhost’=PASSWORD(‘password’);
Joshua says
Just wanted to say “thank you” – this just saved me a ton of time and trouble.
Emdad Shaon says
Thanx man……changing mysql password fix my problem…. RESPECT
Joe says
Where can I find the password for a mysql database?
Editorial Staff says
This is in your cPanel.
Admin
Jamie says
What should I do if it won’t let me log into my cpanel either?
Editorial Staff says
Contact your web hosting provider.
Admin
TP says
Great tip I was able to login through backend and reload my site with no more error messages. Took five minutes! Thanks.
Geeky says
Thank you, changing password and username worked!
YF says
THANKS A LOT!!!!
This really helped me.
Markus says
After editing the wp-config.php and updating with new credentials, the error was still present. I had also to clear my APC opcode cache!
Evik says
Hi,
thank you for this article. I got this error twice and each time I tried to login into my cpanel it helped. Nothing else, but log into the cpanel resolved my problem.
It does not make sense, and I have no idea what is going on.
I got the message every time after I have made some changes on the website (the last time I was putting on a new email subscription).
Ben Nafi says
Thanks sharing..
Thats helped me..
Rae says
Aside from updating wp-config.php, I had to update the domain for the following tables:
wp_blogs
wp_site
wp_options -> option_value (for option_name siteurl, home)
If you use WPMU, you will need to update ALL wp_options tables.
The error would NOT go away until all of this was done.
sara says
This happened to our site the other day, we got the dreaded error! We received a large amount of traffic but it was expected. We were using Quick Cache as the plugin and the hosts changed it for Super cache and also told us we had hit MySQL max_user_connections due to the queries on the wp_options table. They told us after installing super cache it’s taken us from 600+ database connections to under 5.
After installing the super cache plugin everything worked great again. Now I am concerned about this happening in future, what can I do to try and prevent this? We will always have a large surge in tarffic and then very quiet moments. How can I be sure the database will be able to cope with such demands?
Thanks
smithers says
i had “error connecting to database” problem twice in the past two days on a wordpress site on an amazon ec2 micro instance. it occurred after sending out a blast email regarding a fund raising campaign and asking people to check out the site, so i assume it was a load-related failure. anyway, the first time it occurred, i tried to restart the database (service mysqld restart), and it shutdown OK but wouldn’t restart. i then restarted apache (service httpd restart) and then restarted the database, and the database and site came back up.
the problem occurred again today, and the database restart worked without having to restart apache.
Editorial Staff says
Are you using a proper caching solution? This shouldn’t happen unless you are receiving a crazy load of traffic.
Admin
Jon says
The scenario you describe is almost certainly caused by your EC2 instance being out of available memory. When you restart Apache a huge chunk of memory is released; only the minimum resources required to get the server up and running are re-allocated when Apache comes back up, then mysqld has plenty of elbow room to start.
A few good places to start fixing this:
1. Check your php.ini memory limit
2. Check your innodb_buffer_pool_size setting in my.cnf
3. Check your swap space
Jamie says
I’m running an Amazon EC2 instance also & restarting apache & then restarting mysqld worked for me too.
Daniel says
I was moving some webspace from an older to a newer server and tested some things, got stuck with this error. This helped, thanks a lot:
update wp_options set option_value=’http://www.newsitename.de’ where option_name=’siteurl’;
Shawn says
Thanks a lot! I was waiting for support from my host for hours…Sundays…but they took too long. My problem was my database password in wp-config, which was different from the real password. I changed it and everything is fine again.
*bookmarked
hanneng says
recently I also face the same problem on my blog at http://www.hanneng.net after moved to a VPS.
the solution is to modify the wp-config.php
define(‘DB_HOST’, ‘localhost:/tmp/mysql.sock’);
tristan says
Thank you so much! I had messed around in my functions php and lost the ability to open my website. in the process of trying to fix this issue I changed my password for database access and had no idea it was the cause for my error establishing database connection. I’m sure this seems fairly simple to someone who is familiar with this web stuff but for someone like me who is just a dabbler it was very frustrating. website works great now! thank you.
XeNNo says
Actually I’ve had a different problem and took me some time to resolve it. My wp after moving from one server to another, editing all files needed (wp-config) started loading on home page nicely. Also the wp-admin section worked like a charm … but still the problem apeared when I started to point on pages and articles … all of theme besides homepage get me the mysql error regarding connection to database….
everything started to work …
So…. looking on the internet I’ve found this article of yours and tried your advices … my problem not getting resolved on any of them.
Somehow … don’t know why… my .htaccess file pointed on another default root document and after editing my .htaccess ….
Thought somebody will need that …
Anne says
MANY many thanks for posting this. Thought I was going to have to start all over. Being one step above novice is not always sufficient! GAH!
Sean Murphy says
Thanks for this post. The adding that line of php code in the first para did the trick for my sites.
Lucy Gage says
Hi there,
I am getting this error every day “Error establishing a network connection”. The site was working perfectly, then after the first day I got up in the morning and check the site and saw the error for the first time. I logged into the crazy domains control panel and the database was missing. I called support and it took them all day to fix the problem, but then the site was ok again.
The next morning the same problem again. I called support again. After a couple of hours the site was back working again.
The next morning – the same problem again. another hour speaking to support, but they don’t actually tell me what the problem is.
I am so worried about this and jsut want the problem fixed. Do you think it could be anything I have done whilst setting up the website, or just a problem with the host?
Editorial Staff says
It could be a number of things. One of the plugins you are using is exhausting the database server. Another reason could be that your host is overselling the shared hosting plan you maybe on. This would result in database connection error.
https://www.wpbeginner.com/wordpress-hosting/ << See this page if you are looking to find a better web host.
Admin
Hayley says
I actually read half of the 2nd paragraph and managed to fix my site… excellent – thanks.
Editorial Staff says
Glad you got it fixed
Admin
Jenn Hunter says
Thank you for writing this article. It helped me when having to reload my WP website from a previous back up.
Damian says
What happened with me is the php.config’s password didn’t match..downloading config.php and putting in the proper password fixed it!
Guest says
Hi, I run WordPress multisite and just went through an update. I have a blog that has a static front page and a separate page for blog entries. When I tried to open the blog page, I got the above message, Error Establishing a Database Connection.
Turned out I needed to click the yellow bar that appears when you do a major WordPress update, to Update Network which synchs everything database-wise on all sites in your Multisite install. Blog page is viewable now and everything’s working fine!
Rob Rawson says
My solution was to install DBVisualizer and what it showed me was that while the dbname was right it was in the wrong case. So changing the db name from wp to WP in my wp-config.php resolved this issue. No idea how this worked in the first place since this was up and running.
Anna Crowe says
This was a well written and thorough article. Thank you. Not everything applied to me, but I was able to troubleshoot and identify the problem using some of these suggestions. I’m praising your name today! Thanks.
Jacob Degeling says
Hi,
I moved my wp-config.php from the dir below the www root into the www root. That brought the site back up. I would prefer the wp-config.php to be outside the www root, so I’ll have to look into why it wasn’t working in the first place.
Thanks for the help.
Jacob
chris says
sql.safe_mode=On in php.ini hosed my multisite install this way. Change it back and the site came up again.
blkbam says
One thing to check on if you are moving from your system to the server and using MySQL is the case of the database name. In my situation the server is in all lowercase while my development is all uppercase. Iit’s a very easy over site.
Editorial Staff says
Good suggestion
Admin
Laura says
I had this error on my site – i called my host who told me that my username was being denied permission to the database.
No idea how this happened as I hadn’t gone near these details. However, they assured me this was a common problem.
Within 1 minute of the phone call ending, my site was back up and running.
Very strange….but glad its working again!
Great article btw! Glad i didnt need to use it in the end but very easy to understand if i had!
Editorial Staff says
Yeah sometimes the cats that work in the servers start having hiccups
Glad that your site is working now.
Admin
RB says
My wordpress site was working fine. Then I got the “Error Establishing the Database Connection” message. Doing a Google search, there was a lot of information on what to do. This was the most helpful to me. It ended up that my database options table had crashed. I repaired it per this post and my wordpress site it works fine again. Thanks!
Asif says
try checking for the php version as well, sometimes it is the php version on the server that could cause the issue.