From 740397fddee96216e83545ac9dbcae798efa9b43 Mon Sep 17 00:00:00 2001
From: Andrew Lamb <andrew@nerdnetworks.org>
Date: Thu, 13 Jun 2024 07:34:08 -0400
Subject: [PATCH] Refine ParquetAccessPlan comments and tests

---
 .../src/datasource/physical_plan/parquet/access_plan.rs     | 6 +++---
 datafusion/core/src/datasource/physical_plan/parquet/mod.rs | 5 ++---
 .../core/src/datasource/physical_plan/parquet/opener.rs     | 2 ++
 3 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/datafusion/core/src/datasource/physical_plan/parquet/access_plan.rs b/datafusion/core/src/datasource/physical_plan/parquet/access_plan.rs
index f51f2c49e896..e15e907cd9b8 100644
--- a/datafusion/core/src/datasource/physical_plan/parquet/access_plan.rs
+++ b/datafusion/core/src/datasource/physical_plan/parquet/access_plan.rs
@@ -384,7 +384,7 @@ mod test {
         let access_plan = ParquetAccessPlan::new(vec![
             RowGroupAccess::Scan,
             RowGroupAccess::Selection(
-                // select / skip all 20 rows in row group 1
+                // specifies all 20 rows in row group 1
                 vec![
                     RowSelector::select(5),
                     RowSelector::skip(7),
@@ -463,7 +463,7 @@ mod test {
     fn test_invalid_too_few() {
         let access_plan = ParquetAccessPlan::new(vec![
             RowGroupAccess::Scan,
-            // select 12 rows, but row group 1 has 20
+            // specify only 12 rows in selection, but row group 1 has 20
             RowGroupAccess::Selection(
                 vec![RowSelector::select(5), RowSelector::skip(7)].into(),
             ),
@@ -484,7 +484,7 @@ mod test {
     fn test_invalid_too_many() {
         let access_plan = ParquetAccessPlan::new(vec![
             RowGroupAccess::Scan,
-            // select 22 rows, but row group 1 has only 20
+            // specify 22 rows in selection, but row group 1 has only 20
             RowGroupAccess::Selection(
                 vec![
                     RowSelector::select(10),
diff --git a/datafusion/core/src/datasource/physical_plan/parquet/mod.rs b/datafusion/core/src/datasource/physical_plan/parquet/mod.rs
index 5e5cc93bc54f..ec21c5504c69 100644
--- a/datafusion/core/src/datasource/physical_plan/parquet/mod.rs
+++ b/datafusion/core/src/datasource/physical_plan/parquet/mod.rs
@@ -156,9 +156,8 @@ pub use writer::plan_to_parquet;
 /// used to implement external indexes on top of parquet files and select only
 /// portions of the files.
 ///
-/// The `ParquetExec` will try and further reduce any provided
-/// `ParquetAccessPlan` further based on the contents of `ParquetMetadata` and
-/// other settings.
+/// The `ParquetExec` will try and reduce any provided `ParquetAccessPlan`
+/// further based on the contents of `ParquetMetadata` and other settings.
 ///
 /// ## Example of providing a ParquetAccessPlan
 ///
diff --git a/datafusion/core/src/datasource/physical_plan/parquet/opener.rs b/datafusion/core/src/datasource/physical_plan/parquet/opener.rs
index 8557c6d5f950..36335863032c 100644
--- a/datafusion/core/src/datasource/physical_plan/parquet/opener.rs
+++ b/datafusion/core/src/datasource/physical_plan/parquet/opener.rs
@@ -238,6 +238,8 @@ fn create_initial_plan(
 
             // check row group count matches the plan
             return Ok(access_plan.clone());
+        } else {
+            debug!("ParquetExec Ignoring unknown extension specified for {file_name}");
         }
     }