Less strict check and rare rename bug

src/Interpreters/MutationsInterpreter.cpp

@@ -777,10 +777,10 @@ bool MutationsInterpreter::Stage::isAffectingAllColumns(const Names & storage_co
 bool MutationsInterpreter::isAffectingAllColumns() const
 {
     auto storage_columns = metadata_snapshot->getColumns().getNamesOfPhysical();
-    for (const auto & stage : stages)
-        if (stage.isAffectingAllColumns(storage_columns))
-            return true;
-    return false;
+    if (stages.empty())
+        throw Exception(ErrorCodes::LOGICAL_ERROR, "Mutation interpreter has no stages");
+
+    return stages.back().isAffectingAllColumns(storage_columns);
 }
 
 }

src/Interpreters/MutationsInterpreter.h

@@ -42,7 +42,7 @@ public:
     /// Only changed columns.
     const Block & getUpdatedHeader() const;
 
-    /// At least one mutation stage affects all columns in storage
+    /// Latest mutation stage affects all columns in storage
     bool isAffectingAllColumns() const;
 
 private:

src/Storages/MergeTree/IMergeTreeDataPart.cpp

@@ -557,7 +557,8 @@ void IMergeTreeDataPart::loadRowsCount()
         /// columns have to be loaded
         for (const auto & column : getColumns())
         {
-            if (column.type->isValueRepresentedByNumber())
+            /// Most trivial types
+            if (column.type->isValueRepresentedByNumber() && !column.type->haveSubtypes())
             {
                 auto size = getColumnSize(column.name, *column.type);
 

src/Storages/MergeTree/MergeTreeDataMergerMutator.cpp

@@ -1478,13 +1478,14 @@ NamesAndTypesList MergeTreeDataMergerMutator::getColumnsForNewDataPart(
         return updated_header.getNamesAndTypesList();
 
     NameSet removed_columns;
-    NameToNameMap renamed_columns;
+    NameToNameMap renamed_columns_to_from;
+    /// All commands are validated in AlterCommand so we don't care about order
     for (const auto & command : commands_for_removes)
     {
         if (command.type == MutationCommand::DROP_COLUMN)
             removed_columns.insert(command.column_name);
         if (command.type == MutationCommand::RENAME_COLUMN)
-            renamed_columns.emplace(command.rename_to, command.column_name);
+            renamed_columns_to_from.emplace(command.rename_to, command.column_name);
     }
     Names source_column_names = source_part->getColumns().getNames();
     NameSet source_columns_name_set(source_column_names.begin(), source_column_names.end());
@@ -1497,17 +1498,49 @@ NamesAndTypesList MergeTreeDataMergerMutator::getColumnsForNewDataPart(
                 it->type = updated_type;
             ++it;
         }
-        else if (source_columns_name_set.count(it->name) && !removed_columns.count(it->name))
+        else
         {
-            ++it;
-        }
-        else if (renamed_columns.count(it->name) && source_columns_name_set.count(renamed_columns[it->name]))
+            if (!source_columns_name_set.count(it->name))
             {
+                /// Source part doesn't have column but some other column
+                /// was renamed to it's name.
+                auto renamed_it = renamed_columns_to_from.find(it->name);
+                if (renamed_it != renamed_columns_to_from.end()
+                    && source_columns_name_set.count(renamed_it->second))
                     ++it;
+                else
+                    it = storage_columns.erase(it);
             }
             else
             {
+                bool was_renamed = false;
+                bool was_removed = removed_columns.count(it->name);
+
+                /// Check that this column was renamed to some other name
+                for (const auto & [rename_to, rename_from] : renamed_columns_to_from)
+                {
+                    if (rename_from == it->name)
+                    {
+                        was_renamed = true;
+                        break;
+                    }
+                }
+
+                /// If we want to rename this column to some other name, than it
+                /// should it's previous version should be dropped or removed
+                if (renamed_columns_to_from.count(it->name) && !was_renamed && !was_removed)
+                    throw Exception(
+                        ErrorCodes::LOGICAL_ERROR,
+                        "Incorrect mutation commands, trying to rename column {} to {}, but part {} already has column {}", renamed_columns_to_from[it->name], it->name, source_part->name, it->name);
+
+
+                /// Column was renamed and no other column renamed to it's name
+                /// or column is dropped.
+                if (!renamed_columns_to_from.count(it->name) && (was_renamed || was_removed))
                     it = storage_columns.erase(it);
+                else
+                    ++it;
+            }
         }
     }
 

src/Storages/MergeTree/MergeTreeDataPartWide.cpp

@@ -240,7 +240,8 @@ void MergeTreeDataPartWide::calculateEachColumnSizes(ColumnSizeByName & each_col
         total_size.add(size);
 
 #ifndef NDEBUG
-        if (rows_count != 0 && column.type->isValueRepresentedByNumber())
+        /// Most trivial types
+        if (rows_count != 0 && column.type->isValueRepresentedByNumber() && !column.type->haveSubtypes())
         {
             size_t rows_in_column = size.data_uncompressed / column.type->getSizeOfValueInMemory();
             if (rows_in_column != rows_count)