arrow is also autoloadable

.github/config/out_of_tree_extensions.cmake

@@ -10,7 +10,8 @@ if (NOT WIN32)
     duckdb_extension_load(arrow
             LOAD_TESTS DONT_LINK
             GIT_URL https://github.com/duckdblabs/arrow
-            GIT_TAG 1b5b9649d28cd7f79496fb3f2e4dd7b03bf90ac5
+            GIT_TAG 1B5B9649D28CD7F79496FB3F2E4DD7B03BF90AC5
+            APPLY_PATCHES
             )
 endif()
 

.github/patches/extensions/arrow/autoload.patch

@@ -0,0 +1,34 @@
+diff --git a/arrow/arrow_extension.cpp b/arrow/arrow_extension.cpp
+index 34a4021..9330c79 100644
+--- a/arrow/arrow_extension.cpp
++++ b/arrow/arrow_extension.cpp
+@@ -10,6 +10,7 @@
+ #include "duckdb/common/arrow/result_arrow_wrapper.hpp"
+ #include "duckdb/common/arrow/arrow_appender.hpp"
+ #include "duckdb/common/arrow/arrow_converter.hpp"
++#include "duckdb/main/extension_util.hpp"
+ #include "duckdb/parser/parsed_data/create_table_function_info.hpp"
+ #include "duckdb/function/table/arrow.hpp"
+ #endif
+@@ -17,19 +18,11 @@
+ namespace duckdb {
+
+ static void LoadInternal(DatabaseInstance &instance) {
+-	Connection con(instance);
+-	con.BeginTransaction();
+-	auto &catalog = Catalog::GetSystemCatalog(*con.context);
+-
+ 	auto to_arrow_fun = ToArrowIPCFunction::GetFunction();
+-	CreateTableFunctionInfo to_arrow_ipc_info(to_arrow_fun);
+-	catalog.CreateTableFunction(*con.context, &to_arrow_ipc_info);
++	ExtensionUtil::RegisterFunction(db, to_arrow_fun);
+
+ 	auto scan_arrow_fun = ArrowIPCTableFunction::GetFunction();
+-	CreateTableFunctionInfo scan_arrow_ipc_info(scan_arrow_fun);
+-	catalog.CreateTableFunction(*con.context, &scan_arrow_ipc_info);
+-
+-	con.Commit();
++	ExtensionUtil::RegisterFunction(db, scan_arrow_fun);
+ }
+
+ void ArrowExtension::Load(DuckDB &db) {

src/include/duckdb/main/extension_entries.hpp

@@ -234,6 +234,7 @@ static constexpr ExtensionEntry EXTENSION_FILE_CONTAINS[] = {{".parquet?", "parq
 
 static constexpr const char *AUTOLOADABLE_EXTENSIONS[] = {
     //    "azure",
+    "arrow",
     "aws",
     "autocomplete",
     "excel",