> ## Documentation Index
> Fetch the complete documentation index at: https://test.pzona.fun/llms.txt
> Use this file to discover all available pages before exploring further.

# Database connection string formats in mkdb

> mkdb generates environment-variable formatted connection strings for PostgreSQL, MySQL, and Redis. Learn the format and how to retrieve or rotate credentials.

When you create a database, mkdb generates a connection string in environment variable format and prints it immediately after creation. The string is ready to paste directly into a `.env` file or use in a shell script. You can also retrieve it at any time using the `mkdb creds` commands.

## Connection string formats

<Tabs>
  <Tab title="PostgreSQL">
    With authentication:

    ```bash theme={null}
    DB_URL=postgresql://dbuser:<password>@localhost:5432/mydb
    ```

    Without authentication (`--no-auth`):

    ```bash theme={null}
    DB_URL=postgresql://postgres@localhost:5432/mydb
    ```
  </Tab>

  <Tab title="MySQL">
    With authentication:

    ```bash theme={null}
    DB_URL=mysql://dbuser:<password>@tcp(localhost:3306)/mydb
    ```

    Without authentication (`--no-auth`):

    ```bash theme={null}
    DB_URL=mysql://root@tcp(localhost:3306)/mydb
    ```
  </Tab>

  <Tab title="Redis">
    With authentication:

    ```bash theme={null}
    DB_URL=redis://:<password>@localhost:6379/0
    ```

    Without authentication (`--no-auth`):

    ```bash theme={null}
    DB_URL=redis://localhost:6379/0
    ```
  </Tab>
</Tabs>

## Retrieving your connection string

Print the connection string for a container to your terminal:

```bash theme={null}
mkdb creds get --name mydb
```

Copy it directly to your clipboard:

```bash theme={null}
mkdb creds copy --name mydb
```

Append it to a `.env` file:

```bash theme={null}
mkdb creds get --name mydb >> .env
```

## Password details

When you create a database with authentication enabled, mkdb generates a random 12-character alphanumeric password. The password is displayed once at creation time and stored encrypted on disk using AES-256-GCM. You can always retrieve it later with `mkdb creds get`.

## Rotating credentials

Generate a new password for an existing container and update it in the database:

```bash theme={null}
mkdb creds rotate --name mydb
```

mkdb generates a fresh 12-character password, updates the running database, re-encrypts and stores the new value, then prints the updated connection string.

<Note>
  Containers created with `--no-auth` do not have a password. Running `mkdb creds rotate` on an unauthenticated container will return an error. You cannot add authentication to a container after creation.
</Note>