[chore] Change default database in example config to sqlite, update docs. (#4174)

As discussed in Matrix chat.

* Change DB in example config to sqlite.
* Clarify config settings which only apply to postgres.
* Update getting started docs; no need to change example config any more.
* In "single board computers" mention SD card corruption risk.

## Checklist

Please put an x inside each checkbox to indicate that you've read and followed it: `[ ]` -> `[x]`

If this is a documentation change, only the first checkbox must be filled (you can delete the others if you want).

- [X] I/we have read the [GoToSocial contribution guidelines](https://codeberg.org/superseriousbusiness/gotosocial/src/branch/main/CONTRIBUTING.md).
- [X] I/we have discussed the proposed changes already, either in an issue on the repository, or in the Matrix chat.
- [X] I/we have not leveraged AI to create the proposed changes.
- [X] I/we have performed a self-review of added code.
- [X] I/we have made any necessary changes to documentation.

Reviewed-on: https://codeberg.org/superseriousbusiness/gotosocial/pulls/4174
Co-authored-by: Phil Hagelberg <phil@hagelb.org>
Co-committed-by: Phil Hagelberg <phil@hagelb.org>

3 files changed, 13 insertions, 15 deletions

diff --git a/docs/configuration/database.md b/docs/configuration/database.md
index 06b6b4f60..223742753 100644
--- a/docs/configuration/database.md
+++ b/docs/configuration/database.md
@@ -2,21 +2,21 @@
 
 GoToSocial stores statuses, accounts, etc, in a database. This can be either [SQLite](https://sqlite.org/index.html) or [Postgres](https://www.postgresql.org/).
 
-By default, GoToSocial will use Postgres, but this is easy to change.
+By default, GoToSocial will use SQLite, but this is easy to change.
 
 ## SQLite
 
 SQLite, as the name implies, is the lightest database type that GoToSocial can use. It stores entries in a simple file format, usually in the same directory as the GoToSocial binary itself. SQLite is great for small instances and single-board computers, where a dedicated database would be overkill.
 
-To configure GoToSocial to use SQLite, change `db-type` to `sqlite`. The `address` setting will then be a filename instead of an address, so you will want to change it to `sqlite.db` or something similar.
+To use SQLite, keep the default `db-type` as `sqlite`. By default the database will be kept in the same directory as the GoToSocial binary, ie., `./sqlite.db`, but you can change this using `db-address` if you want to keep it somewhere else. In the same directory as the `sqlite.db` file, the SQLite driver will also create files `sqlite.db-wal` and `sqlite.db-shm` for temporary storage.
 
 Note that the `:memory:` setting will use an *in-memory database* which will be wiped when your GoToSocial instance stops running. This is for testing only and is absolutely not suitable for running a proper instance, so *don't do this*.
 
 ## Postgres
 
-Postgres is a heavier database format, which is useful for larger instances where you need to scale performance, or where you need to run your database on a dedicated machine separate from your GoToSocial instance (or do funky stuff like run a database cluster).
+Postgres (aka PostgreSQL) is a heavier database which is useful for larger instances where you need to run your database on a dedicated machine separate from your GoToSocial instance (or do funky stuff like run a database cluster).
 
-You can connect to Postgres using either a Unix socket connection, or via TCP, depending on what you've set as your `db-address` value.
+To configure GoToSocial to use Postgres, change `db-type` to `postgres`. The `db-address` setting will then be either a Unix socket connection or a hostname.
 
 GoToSocial also supports connecting to Postgres using SSL/TLS over TCP. If you're running Postgres on a different machine from GoToSocial, and connecting to it via an IP address or hostname (as opposed to just running on localhost), then SSL/TLS is **CRUCIAL** to avoid leaking data all over the place!
 
@@ -71,8 +71,8 @@ db-postgres-connection-string: 'postgres://myUser:myPass@localhost/db?search_pat
 
 # String. Database type.
 # Options: ["postgres","sqlite"]
-# Default: "postgres"
-db-type: "postgres"
+# Default: "sqlite"
+db-type: "sqlite"
 
 # String. Database address or parameters.
 #
@@ -87,29 +87,29 @@ db-type: "postgres"
 #
 # Examples: ["localhost","my.db.host","127.0.0.1","192.111.39.110",":memory:", "sqlite.db"]
 # Default: ""
-db-address: ""
+db-address: "sqlite.db"
 
-# Int. Port for database connection.
+# Int. Port for postgres database connection; ignored for sqlite.
 # Examples: [5432, 1234, 6969]
 # Default: 5432
 db-port: 5432
 
-# String. Username for the database connection.
+# String. Username for postgres database connection.
 # Examples: ["mydbuser","postgres","gotosocial"]
 # Default: ""
 db-user: ""
 
-# String. Password to use for the database connection
+# String. Password to use for postgres database connection.
 # Examples: ["password123","verysafepassword","postgres"]
 # Default: ""
 db-password: ""
 
-# String. Name of the database to use within the provided database type.
+# String. Name of the database to use for postgres database connection.
 # Examples: ["mydb","postgres","gotosocial"]
 # Default: "gotosocial"
 db-database: "gotosocial"
 
-# String. Disable, enable, or require SSL/TLS connection to the database.
+# String. Disable, enable, or require SSL/TLS connection to postgres.
 # If "disable" then no TLS connection will be attempted.
 # If "enable" then TLS will be tried, but the database certificate won't be checked (for self-signed certs).
 # If "require" then TLS will be required to make a connection, and a valid certificate must be presented.
diff --git a/docs/getting_started/index.md b/docs/getting_started/index.md
index 286a2e4fd..e99e069e3 100644
--- a/docs/getting_started/index.md
+++ b/docs/getting_started/index.md
@@ -55,7 +55,7 @@ For media storage, including [storage of remote media files in the cache](../adm
 
 ### Single-board Computers
 
-GoToSocial's light system requirements means that it runs pretty well on decently-specced single-board computers. If running on a single-board computer, you should ensure that GoToSocial is using a USB drive (preferably an SSD) to store its database files and media, not SD card storage, since the latter tends to be too slow to run a database on.
+GoToSocial's light system requirements means that it runs pretty well on decently-specced single-board computers. If running on a single-board computer, you should ensure that GoToSocial is using a USB drive (preferably an SSD) to store its database files and media, not SD card storage, since the latter tends to be too slow to run a database on and can easily get corrupted with write-heavy workloads.
 
 ### VPS
 
diff --git a/docs/getting_started/installation/metal.md b/docs/getting_started/installation/metal.md
index 093f0e678..563522918 100644
--- a/docs/getting_started/installation/metal.md
+++ b/docs/getting_started/installation/metal.md
@@ -63,8 +63,6 @@ You'll probably need to change the following settings:
 
 - Set `host` to whatever hostname you're going to be running the server on (eg., `example.org`).
 - Set `port` to `443`.
-- Set `db-type` to `sqlite`.
-- Set `db-address` to `sqlite.db`.
 - Set `storage-local-base-path` to the storage directory you created above (eg., `/gotosocial/storage`).
 - Set `letsencrypt-enabled` to `true`.
 - Set `letsencrypt-cert-dir` to the certificate storage directory you created above (eg., `/gotosocial/storage/certs`).