Error establishing a database connection

Hello everyone.

My Wordpress website in the past has worked perfectly fine. However, I have noticed recently as I have started submitting job applications and people have been frequenting my site, that it is starting to go down quite a bit.

When it is down, I get this error:
Error establishing a database connection

I’ve checked the wp-config.php and everything appears to be entered correctly. I’ve put a ticket in with Dreamhost, but has anyone experienced a similar error?

It is not permanently down, it just seems to go offline and online randomly. At the present moment 12/16 13:07, it is down. But about 10 minutes earlier it was running perfectly fine.