add direct connect docs (#26)

Co-authored-by: Marcelo Trylesinski <[email protected]>

docs/guides/advanced/06_direct_database_connections.md

@@ -1,2 +1,44 @@
-!!! warning "🚧 Work in Progress 🚧"
-    This page is yet to be written, [contact us](../../help.md) if you have any questions.
+# Direct Database Connections
+
+The **Logfire** platform allows you to connect and run SQL queries against your data using PostgreSQL syntax.
+
+By doing this, you can connect your existing tools such as Grafana, Metabase, Superset, or anything else with support for querying PostgreSQL sources.
+
+## Generating credentials
+
+To connect, you'll first need to generate generate database credentials from your project page at `https://logfire.pydantic.dev/<organization>/<project>/settings/database-credentials`
+
+![Creating database credentials](../../images/guide/direct-connect-credentials.png)
+
+The credentials generated are a PostgreSQL URI which can be used as a connection string for compatible tools. These will only be shown by the Logfire platform once, so save them to a secure location for future use!
+
+## Example: pgcli
+
+[`pgcli`](https://www.pgcli.com/) is a command-line tool to access PostgreSQL databases.
+
+Using the credentials generated in the previous step as the argument to `pgcli`, you can connect directly to **Logfire**:
+
+```
+$ pgcli postgresql://<user>:<password>@db.logfire.dev:5432/proj_david-test  # REDACTED
+Version: 4.0.1
+Home: http://pgcli.com
+proj_david-test> select start_timestamp, message from records limit 10;
++-------------------------------+----------------------------------------+
+| start_timestamp               | message                                |
+|-------------------------------+----------------------------------------|
+| 2024-04-28 10:50:41.681886+00 | action=view-faq size=549 i=0           |
+| 2024-04-28 10:50:41.711747+00 | GET /contact/ http send response.body  |
+| 2024-04-28 10:50:41.665576+00 | GET /contact/                          |
+| 2024-04-28 10:50:41.711119+00 | GET /contact/ http send response.start |
+| 2024-04-28 10:50:41.709458+00 | response 500                           |
+| 2024-04-28 10:50:38.50534+00  | action=view-cart size=517 i=0          |
+| 2024-04-28 10:50:39.446668+00 | action=view-faq size=637 i=2           |
+| 2024-04-28 10:50:38.681198+00 | action=view-terms size=216 i=3         |
+| 2024-04-28 10:50:39.416706+00 | action=view-product size=380 i=0       |
+| 2024-04-28 10:50:38.394237+00 | sub-sub-sub-action=logout              |
++-------------------------------+----------------------------------------+
+SELECT 10
+Time: 0.218s
+```
+
+With the flexibility of PostgreSQL access available to you, we can't wait to hear what you do with the Logfire platform!