Warning: mysqli_connect(): (HY000/1049): Unknown database Error

I am in trouble to face this issue for connection of mysql.

using: nginx, php, mysql(mariadb) and phpmyadmin

I am trying to create my first php with mysql application using docker compose. For so I have my own application and create 1 file as Dockerfile and docker-compose.yml file to compose it by using command ‘docker-compose up’. And mysql is using volumes of docker container.

The page I can check SQL connection shows "**Warning: mysqli_connect(): (HY000/1049): Unknown database 'local_neotaoclg' in /var/www/**....”

It looks socket issue as these article. ( Please bid on my project only expert who can understand like this article. I need Docker, mysql and php expert! )
[https://stackoverflow.com/questions/47272072/celery-workers-unable-to-connect-to-redis-on-docker-instances/47273294#47273294](https://stackoverflow.com/questions/47272072/celery-workers-unable-to-connect-to-redis-on-docker-instances/47273294#47273294)

or may be mysql and phpmyadmin connection is not working?

I'm looking for someone who can check on my local by anydesk or teamviewer.

I can share Dockerfile, docker-compose.yaml,my.cnf and php.ini too.