Update README.md

Author: InstaZDLL

README.md

@@ -40,6 +40,7 @@ The following environment variables can be set when running the Docker container
 | WORDPRESS\_DATABASE\_PASSWORD | wpuser | mypassword | The password for the WordPress database. |
 | WORDPRESS\_DATABASE\_HOST | localhost | example.com or 64.23.50.120 | The ip address of the WordPress database, can be private, public or you can use a domain. |
 | WORDPRESS\_HOST | localhost | example.com or 64.23.50.120 | The host of your WordPress site. If this is not set or is empty, it will default to <strong>localhost</strong>. This means that all resources will only be available on localhost. To make your WordPress site work online, change this variable to the public IP address or domain name of your host. |
+| WORDPRESS\_COMPOSE | false | true | If you use this image in a docker compose, you must set this variable to true, this will delay wordpress startup to allow the database container to initialize and avoid the database not found error on wordpress. |
 
 ⚠️ **Important :** The var `WORDPRESS_DATABASE_HOST` it can't be `localhost` you must change this variable or the container will be stopped, if you have a database container change to host or container ip. ⚠️