From 0041fdf497b2c7780fe5bcb3eabe54b71ded40fa Mon Sep 17 00:00:00 2001
From: Nikita Taranov <nikita.taranov@clickhouse.com>
Date: Sun, 1 Dec 2024 18:50:55 +0100
Subject: [PATCH] impl

---
 src/Interpreters/executeQuery.cpp               |  2 +-
 ...l_format_matching_case_insensitive.reference |  1 +
 ...276_null_format_matching_case_insensitive.sh | 17 +++++++++++++++++
 3 files changed, 19 insertions(+), 1 deletion(-)
 create mode 100644 tests/queries/0_stateless/03276_null_format_matching_case_insensitive.reference
 create mode 100755 tests/queries/0_stateless/03276_null_format_matching_case_insensitive.sh

diff --git a/src/Interpreters/executeQuery.cpp b/src/Interpreters/executeQuery.cpp
index a94eca3d7b1..29280c91f1a 100644
--- a/src/Interpreters/executeQuery.cpp
+++ b/src/Interpreters/executeQuery.cpp
@@ -1538,7 +1538,7 @@ std::pair<ASTPtr, BlockIO> executeQuery(
                 ? getIdentifierName(ast_query_with_output->format)
                 : context->getDefaultFormat();
 
-        if (format_name == "Null")
+        if (boost::iequals(format_name, "Null"))
             res.null_format = true;
     }
 
diff --git a/tests/queries/0_stateless/03276_null_format_matching_case_insensitive.reference b/tests/queries/0_stateless/03276_null_format_matching_case_insensitive.reference
new file mode 100644
index 00000000000..d00491fd7e5
--- /dev/null
+++ b/tests/queries/0_stateless/03276_null_format_matching_case_insensitive.reference
@@ -0,0 +1 @@
+1
diff --git a/tests/queries/0_stateless/03276_null_format_matching_case_insensitive.sh b/tests/queries/0_stateless/03276_null_format_matching_case_insensitive.sh
new file mode 100755
index 00000000000..d1736d58832
--- /dev/null
+++ b/tests/queries/0_stateless/03276_null_format_matching_case_insensitive.sh
@@ -0,0 +1,17 @@
+#!/usr/bin/env bash
+
+set -e
+
+CUR_DIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
+# shellcheck source=../shell_config.sh
+. "$CUR_DIR"/../shell_config.sh
+
+query_id="03276_null_format_matching_case_insensitive_$RANDOM$RANDOM"
+$CLICKHOUSE_CLIENT --query_id "$query_id" -q "select * from numbers_mt(1e8) format null"
+
+$CLICKHOUSE_CLIENT -q "
+  SYSTEM FLUSH LOGS;
+
+  -- SendBytes should be close to 0, previously for this query it was around 800MB
+  select ProfileEvents['NetworkSendBytes'] < 1e6 from system.query_log where current_database = currentDatabase() and event_date >= yesterday() and query_id = '$query_id' and type = 'QueryFinish';
+"