I have just started a new Symfony 5 project (only worked on Symfony 3 before) and I am having a hard time to understand how values in `.env` and `.env.local` work together.

The Symfony docs say, that values in `.env.local` will override values from `.env`:

> 
> If you need to override an environment value (e.g. to a different
> value on your local machine), you can do that in a .env.local file:
> 
> 
> 

All machines I am working on use the same basic setup (same DB server, etc.) but some values are different (DB name, password, etc.). Thus I wanted to put the common configuration in `.env` and the device specific values in `.env.local`:

```
# .env
...
DB_SERVER="localhost"
DB_VERSION="10.4"

DB_USER=${DB_DBNAME}

DATABASE_URL="mysql://${DB_USER}:${DB_PASS}@${DB_SERVER}/${DB_DBNAME}?serverVersion=${DB_VERSION}"

```

```
# .env.local
DB_DBNAME="someDB"
DB_PASS="secretPW"

```

When using this setup I get an error and `php bin/console debug:container --env-vars` shows `DATABASE_URL "mysql://:@localhost/?serverVersion=10.4"`. Obviously `DATABASE_URL` is build ignoring the values from `.env.local`.

I can easily solve this by moving `DATABASE_URL="mysql://...` to `.env.local` but is this the intended way of using `.env` and `.env.local`?

I thought values of these files are merged where `.env.local` values override `.env` values. Is this not the case? Or did I make some error?