docs(database): show the setup SQL by default in Returning data sets

The tab group defaulted to Data, so a reader going top to bottom never saw
the create table statements and hit 'type planets does not exist' at the next
snippet. The Data tab is an illustration. The SQL tab is the part you run.

Adjusts the lead-in sentence so it still introduces both tabs.

apps/docs/content/guides/database/functions.mdx

@@ -158,13 +158,13 @@ Reference: [`Rpc()`](../../reference/csharp/rpc)
 
 A database function can also return a data set from a [table](../../guides/database/tables) or a view.
 
-For example, take a database holding some Star Wars data:
+For example, create two tables holding some Star Wars data. The **Data** tab shows the rows they end up with.
 
 <Tabs
   scrollable
   size="small"
   type="underlined"
-  defaultActiveId="data"
+  defaultActiveId="sql"
   queryGroup="example-view"
 >
 <TabPanel id="data" label="Data">