Docs on entra auth for pgadmin

docs/using_entra_auth.md

@@ -2,7 +2,10 @@
 
 To follow security best practices, this project is setup to use passwordless authentication with the Azure Database for PostgreSQL Flexible Server. This means that you can't connect to the database with a password, but instead need to use a token associated with a Microsoft Entra user. Locally, the user should be your own Azure account, whichever account was used to run `azd up`. In production, the user will be the managed identity assigned to the Azure Container App.
 
-## Using psql with Entra auth
+* [Using Entra auth with psql](#using-entra-auth-with-psql)
+* [Using Entra auth with pgAdmin](#using-entra-auth-with-pgadmin)
+
+## Using Entra auth with psql
 
 1. Make sure you are logged into the Azure Developer CLI with the same account that was used to run `azd up`.
 
@@ -45,3 +48,59 @@ To follow security best practices, this project is setup to use passwordless aut
     ```
 
 5. In psql, use `\d` to list the tables. When you `SELECT` from a table, select only the columns you're interested in, to avoid rendering the vector embeddings in the terminal.
+
+## Using Entra auth with pgAdmin
+
+1. Make sure you are logged into the Azure Developer CLI with the same account that was used to run `azd up`.
+
+    ```shell
+    azd auth login
+    ```
+
+    If you used a non-default tenant to run `azd up`, you may need to specify the tenant ID:
+
+    ```shell
+    azd auth login --tenant-id {tenant_id}
+    ```
+
+2. Generate a token for the Azure Database for PostgreSQL Flexible Server.
+
+    ```shell
+    azd auth token --scope https://ossrdbms-aad.database.windows.net/.default --output json
+    ```
+
+    Once again, if you used a non-default tenant to run `azd up`, you may need to specify the tenant ID.
+
+    ```shell
+    azd auth token --scope https://ossrdbms-aad.database.windows.net/.default --tenant-id YOUR-TENANT-ID --output json
+    ```
+
+    This will output JSON with a token inside the "token" field. Copy the token.
+
+3. Open pgAdmin and create a new server connection.
+
+4. In the "General" tab, set the name to something memorable like "RAG PostgreSQL server".
+
+5. In the "Connection" tab, set the host to the `POSTGRES_HOST` value from the current `azd` environment. Run:
+
+    ```shell
+    azd env get-value POSTGRES_HOST
+    ```
+
+6. Set the database to the `POSTGRES_DATABASE` value from the current `azd` environment. Run:
+
+    ```shell
+    azd env get-value POSTGRES_DATABASE
+    ```
+
+7. Set the username to the `POSTGRES_USERNAME` value from the current `azd` environment. Run:
+
+    ```shell
+    azd env get-value POSTGRES_USERNAME
+    ```
+
+8. Set the password to the token you generated in step 2. You will need to refresh that password with a new token periodically (every few hours).
+
+9. Now you should be able to connect to the database and view the tables and data.
+
+    ![Screenshot of pgAdmin showing the tables in the database](images/screenshot_pgadmin.png)