test: reproducer for missing field metadata in left hand NULL field o…

…f union

datafusion/sqllogictest/src/test_context.rs

@@ -314,8 +314,13 @@ pub async fn register_metadata_tables(ctx: &SessionContext) {
         String::from("metadata_key"),
         String::from("the name field"),
     )]));
+    let l_name =
+        Field::new("l_name", DataType::Utf8, true).with_metadata(HashMap::from([(
+            String::from("metadata_key"),
+            String::from("the l_name field"),
+        )]));
 
-    let schema = Schema::new(vec![id, name]).with_metadata(HashMap::from([(
+    let schema = Schema::new(vec![id, name, l_name]).with_metadata(HashMap::from([(
         String::from("metadata_key"),
         String::from("the entire schema"),
     )]));
@@ -325,6 +330,7 @@ pub async fn register_metadata_tables(ctx: &SessionContext) {
         vec![
             Arc::new(Int32Array::from(vec![Some(1), None, Some(3)])) as _,
             Arc::new(StringArray::from(vec![None, Some("bar"), Some("baz")])) as _,
+            Arc::new(StringArray::from(vec![None, Some("l_bar"), Some("l_baz")])) as _,
         ],
     )
     .unwrap();

datafusion/sqllogictest/test_files/metadata.slt

@@ -25,7 +25,7 @@
 ## with metadata in SQL.
 
 query IT
-select * from table_with_metadata;
+select id, name from table_with_metadata;
 ----
 1 NULL
 NULL bar
@@ -110,6 +110,14 @@ FROM
 ----
 6
 
+# Regression test: missing field metadata, from the NULL field on the left side of the union
+statement error DataFusion error: Internal error: Physical input schema should be the same as the one converted from logical input schema..
+(SELECT id, NULL::string as name, l_name FROM "table_with_metadata")
+  UNION
+(SELECT id, name, NULL::string as l_name FROM "table_with_metadata")
+ORDER BY id, name, l_name;
+
+
 
 statement ok
 drop table table_with_metadata;