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Author: gbrgr

crates/iceberg/src/arrow/record_batch_transformer.rs

@@ -531,6 +531,8 @@ impl RecordBatchTransformer {
             PrimitiveLiteral::String(_) => {
                 // Use Run-End Encoding for constant strings (memory efficient)
                 let run_ends_field = Arc::new(Field::new("run_ends", DataType::Int32, false));
+                // Note that this is nullable, as Arrow expects this when building the
+                // final Arrow schema.
                 let values_field = Arc::new(Field::new("values", DataType::Utf8, true));
                 DataType::RunEndEncoded(run_ends_field, values_field)
             }