diff --git a/src/Storages/ObjectStorage/StorageObjectStorageSource.cpp b/src/Storages/ObjectStorage/StorageObjectStorageSource.cpp
index 07ef358d0396..25cb2d001c46 100644
--- a/src/Storages/ObjectStorage/StorageObjectStorageSource.cpp
+++ b/src/Storages/ObjectStorage/StorageObjectStorageSource.cpp
@@ -889,7 +889,7 @@ StorageObjectStorageSource::ReaderHolder StorageObjectStorageSource::createReade
 
         InputFormatPtr input_format;
         if (context_->getSettingsRef()[Setting::use_parquet_metadata_cache] && use_native_reader_v3
-            && (object_info->getFileFormat().value_or(configuration->getFormat()) == "Parquet")
+            && (Poco::toLower(object_info->getFileFormat().value_or(configuration->getFormat())) == "parquet")
             && !object_info->getObjectMetadata()->etag.empty())
         {
             std::optional<RelativePathWithMetadata> object_with_metadata = object_info->relative_path_with_metadata;
diff --git a/tests/integration/test_storage_iceberg_with_spark/test_read_constant_columns_optimization.py b/tests/integration/test_storage_iceberg_with_spark/test_read_constant_columns_optimization.py
index ae9044e86e52..58ac641f0074 100644
--- a/tests/integration/test_storage_iceberg_with_spark/test_read_constant_columns_optimization.py
+++ b/tests/integration/test_storage_iceberg_with_spark/test_read_constant_columns_optimization.py
@@ -169,6 +169,18 @@ def execute_spark_query(query: str):
     for replica in started_cluster_iceberg_with_spark.instances.values():
         replica.query("SYSTEM FLUSH LOGS")
 
+    # Number of object-get requests per data file that are NOT served from caches
+    # after the warmup query above. The parquet metadata cache (enabled by default)
+    # caches the parquet footer keyed by the object's etag; the warmup query then
+    # populates it, so any subsequent read of the same file skips one object-get
+    # (the footer read). However, AzureObjectStorage::getObjectMetadata does NOT
+    # populate etag, so the cache guard `!etag.empty()` in
+    # StorageObjectStorageSource::createReader always fails for Azure, and the
+    # cache path is never taken there. As a result the multiplier is:
+    #   S3:    2 (footer served from cache, data-only gets remain)
+    #   Azure: 3 (cache never engaged, footer + data gets)
+    per_file_gets = 2 if storage_type == "s3" else 3
+
     def check_events(query_id, event, is_cluster, expected):
         res = instance.query(
             f"""