fix doc test and add more doc

datafusion/catalog/src/dynamic_file/catalog.rs

@@ -15,7 +15,8 @@
 // specific language governing permissions and limitations
 // under the License.
 
-//! dynamic_file contains a SchemaProvider that creates tables from file paths
+//! dynamic_file contains [`DynamicFileCatalog`] that creates tables from file paths
+//! if the wrapped [`CatalogProviderList`] doesn't have the table provider.
 
 use crate::{CatalogProvider, CatalogProviderList, SchemaProvider, TableProvider};
 use async_trait::async_trait;
@@ -24,8 +25,11 @@ use dirs::home_dir;
 use std::any::Any;
 use std::sync::Arc;
 
+/// Wrap another catalog provider list
 pub struct DynamicFileCatalog {
+    /// The inner catalog provider list
     inner: Arc<dyn CatalogProviderList>,
+    /// The factory that can create a table provider from the file path
     factory: Arc<dyn UrlTableFactory>,
 }
 
@@ -67,7 +71,9 @@ impl CatalogProviderList for DynamicFileCatalog {
 
 /// Wraps another catalog provider
 struct DynamicFileCatalogProvider {
+    /// The inner catalog provider
     inner: Arc<dyn CatalogProvider>,
+    /// The factory that can create a table provider from the file path
     factory: Arc<dyn UrlTableFactory>,
 }
 
@@ -112,7 +118,9 @@ impl CatalogProvider for DynamicFileCatalogProvider {
 /// The provider will try to create a table provider from the file path if the table provider
 /// isn't exist in the inner schema provider. The required object store must be registered in the session context.
 pub struct DynamicFileSchemaProvider {
+    /// The inner schema provider
     inner: Arc<dyn SchemaProvider>,
+    /// The factory that can create a table provider from the file path
     factory: Arc<dyn UrlTableFactory>,
 }
 

datafusion/core/src/datasource/dynamic_file.rs

@@ -15,7 +15,8 @@
 // specific language governing permissions and limitations
 // under the License.
 
-//! dynamic_file_schema contains a SchemaProvider that creates tables from file paths
+//! dynamic_file_schema contains an [`UrlTableFactory`] implementation that
+//! can create a [`ListingTable`] from the given url.
 
 use std::sync::Arc;
 
@@ -31,6 +32,7 @@ use crate::execution::context::SessionState;
 /// [DynamicListTableFactory] is a factory that can create a [ListingTable] from the given url.
 #[derive(Default)]
 pub struct DynamicListTableFactory {
+    /// The session store that contains the current session.
     session_store: Arc<SessionStore>,
 }
 

datafusion/core/src/execution/context/mod.rs

@@ -324,7 +324,7 @@ impl SessionContext {
     }
 
     /// Enable the dynamic file query for the current session.
-    /// See [DynamicFileSchemaProvider] for more details
+    /// See [DynamicFileCatalog] for more details
     ///
     /// # Example: query the url table
     ///
@@ -343,7 +343,7 @@ impl SessionContext {
     /// assert_batches_eq!(
     ///  &[
     ///    "+---+----------------+",
-    ///    "| a | MIN(example.b) |",
+    ///    "| a | min(example.b) |",
     ///    "+---+----------------+",
     ///    "| 1 | 2              |",
     ///    "+---+----------------+",