Merge pull request ClickHouse#78858 from azat/rmv-alter-crash-fix

Fix crash in REFRESHABLE MV in case of ALTER after incorrect shutdown

Author: azat

src/Storages/MaterializedView/RefreshTask.cpp

@@ -216,6 +216,8 @@ void RefreshTask::checkAlterIsPossible(const DB::ASTRefreshStrategy & new_strate
 
 void RefreshTask::alterRefreshParams(const DB::ASTRefreshStrategy & new_strategy)
 {
+    StorageID view_storage_id = StorageID::createEmpty();
+
     {
         std::lock_guard guard(mutex);
 
@@ -235,9 +237,17 @@ void RefreshTask::alterRefreshParams(const DB::ASTRefreshStrategy & new_strategy
         refresh_settings = {};
         if (new_strategy.settings != nullptr)
             refresh_settings.applyChanges(new_strategy.settings->changes);
+
+        if (view)
+            view_storage_id = view->getStorageID();
     }
+
     /// In case refresh period changed.
-    view->getContext()->getRefreshSet().notifyDependents(view->getStorageID());
+    if (view_storage_id)
+    {
+        const auto & refresh_set = Context::getGlobalContextInstance()->getRefreshSet();
+        refresh_set.notifyDependents(view_storage_id);
+    }
 }
 
 RefreshTask::Info RefreshTask::getInfo() const