Adding information on D1PreparedStatement object.

Author: Oxyjun

src/content/docs/d1/worker-api/d1-database.mdx

@@ -35,7 +35,8 @@ const stmt = env.DB.prepare("SELECT * FROM Customers WHERE CompanyName = ?").bin
 
 #### Return values
 
-- None.
+- <code>D1PreparedStatement</code>: <Type text="Object"/>
+  - An object which only contains methods `bind`,`run`, `raw`, and `first`.
 
 #### Guidance
 

src/content/docs/d1/worker-api/prepared-statements.mdx

@@ -23,7 +23,7 @@ const returnValue = await stmt.run();
 
 - None.
 
-#### Return value
+#### Return values
 
 - <code>D1Result</code>: <Type text="Object"/>
   - An object containing the success status, a meta object, and an array of objects containing the query results.