Error establishing a database connection

[akshayan]

Maybe:

Common MySQL Connection Errors

Many websites use MySQL databases to store information and settings. However, there are some reasons why the connection to the database may fail. This article describes some commonly seen error messages when connecting to a database, as well as some general tips to keep in mind when setting up a database connection. Common Error Messages Using MySQL is great, but the error message returned if there is an issue logging in to your database can be quite confusing. Here are some commonly seen error…

If that doesn’t help, check out this.

"Random" Error establishing a database connection error on TMAC PowerStore

Really weird now my website shows white screen and loads way way slower but after still loads. Still not sure what caused that Database Error but maybe my plugin WP-Optimize which optimize my database. I will try to disable that functionality to optimize the database and see.