Remove dictionary_batch_extreme; use min_max_batch_generic

Refactor the code to eliminate the dictionary_batch_extreme.
Directly pass dictionary arrays through min_max_batch_generic
for improved clarity and efficiency.

Author: kosiew

datafusion/functions-aggregate-common/src/min_max.rs

@@ -465,14 +465,6 @@ fn scalar_extreme(values: &ArrayRef, ordering: Ordering) -> Result<Option<Scalar
     Ok(extreme)
 }
 
-fn dictionary_batch_extreme(
-    values: &ArrayRef,
-    ordering: Ordering,
-) -> Result<ScalarValue> {
-    scalar_extreme(values, ordering)?
-        .map_or_else(|| ScalarValue::try_from(values.data_type()), Ok)
-}
-
 fn wrap_dictionary_scalar(key_type: &DataType, value: ScalarValue) -> ScalarValue {
     ScalarValue::Dictionary(Box::new(key_type.clone()), Box::new(value))
 }
@@ -820,9 +812,7 @@ pub fn min_batch(values: &ArrayRef) -> Result<ScalarValue> {
         DataType::FixedSizeList(_, _) => {
             min_max_batch_generic(values, Ordering::Greater)?
         }
-        DataType::Dictionary(_, _) => {
-            dictionary_batch_extreme(values, Ordering::Greater)?
-        }
+        DataType::Dictionary(_, _) => min_max_batch_generic(values, Ordering::Greater)?,
         _ => min_max_batch!(values, min),
     })
 }
@@ -882,7 +872,7 @@ pub fn max_batch(values: &ArrayRef) -> Result<ScalarValue> {
         DataType::List(_) => min_max_batch_generic(values, Ordering::Less)?,
         DataType::LargeList(_) => min_max_batch_generic(values, Ordering::Less)?,
         DataType::FixedSizeList(_, _) => min_max_batch_generic(values, Ordering::Less)?,
-        DataType::Dictionary(_, _) => dictionary_batch_extreme(values, Ordering::Less)?,
+        DataType::Dictionary(_, _) => min_max_batch_generic(values, Ordering::Less)?,
         _ => min_max_batch!(values, max),
     })
 }