We you want to customise your Error Establishing Database Connection to something else then you need to create a file. Here is the documentation for that https://yoast.com/custom-wordpress-database-error-pages/
In this case, I had to reset the some of the file permissions of the WP install to 775. The the fault was with the managed hosting provider having this problem with many of their multisite installs.
It is not absolutely necessary to add anything to the config file. However it’s a good idea to do a test to look for any unsecured Http calls, such as stylesheets or Scripts. A good resource for this is https://www.whynopadlock.com/. The force SSL Setting can sometimes help with requests coming from plug-ins or anything you … Read more
Have you set the constants WP_CONTENT_FOLDERNAME and WP_CONTENT_DIR ? If not, that’s likely to be your problem.
I changed the password for the database user of my website, updated wp-config.php and wordpress asks to be reinstalled
A database error can occur for many reasons. It’s usually the result of an incorrect database address, username, or password. It’s likely not a timeout failure, since WordPress has a separate error for that. Here are two common issues: DB Configuration Since you have intermittent failures, this likely points to an issue with the database … Read more
Can wp-config move cause dashboard not to load?
Did you check if the table prefixe in wp-config is same as per your database.. To check the table prefix of your database go to phpmyadmin. Click on your database and expand it If you notice in following image , you will find out that all the table have prefix “wp_” .. so that means … Read more
Duplicate WP Migration affecting site on separate domain?
So your Git repository was initialized in the wrong place. If you have the initial files, you can go back there and try again making sure the git repo is in the actualy document root and make sure all of the files are tracked. If you do not you can do a fresh install of … Read more