diff --git a/src/Columns/ColumnLowCardinality.cpp b/src/Columns/ColumnLowCardinality.cpp
index 11d02b023d6..4f9ab8215be 100644
--- a/src/Columns/ColumnLowCardinality.cpp
+++ b/src/Columns/ColumnLowCardinality.cpp
@@ -485,13 +485,8 @@ void ColumnLowCardinality::setSharedDictionary(const ColumnPtr & column_unique)
 ColumnLowCardinality::MutablePtr ColumnLowCardinality::cutAndCompact(size_t start, size_t length) const
 {
     auto sub_positions = IColumn::mutate(idx.getPositions()->cut(start, length));
-    /// Create column with new indexes and old dictionary.
-    /// Dictionary is shared, but will be recreated after compactInplace call.
-    auto column = ColumnLowCardinality::create(getDictionary().assumeMutable(), std::move(sub_positions));
-    /// Will create new dictionary.
-    column->compactInplace();
-
-    return column;
+    auto new_column_unique = Dictionary::compact(dictionary.getColumnUnique(), sub_positions);
+    return ColumnLowCardinality::create(std::move(new_column_unique), std::move(sub_positions));
 }
 
 void ColumnLowCardinality::compactInplace()
@@ -589,7 +584,7 @@ size_t ColumnLowCardinality::Index::getSizeOfIndexType(const IColumn & column, s
                     column.getName());
 }
 
-void ColumnLowCardinality::Index::attachPositions(ColumnPtr positions_)
+void ColumnLowCardinality::Index::attachPositions(MutableColumnPtr positions_)
 {
     positions = std::move(positions_);
     updateSizeOfType();
@@ -820,21 +815,23 @@ void ColumnLowCardinality::Dictionary::setShared(const ColumnPtr & column_unique
     shared = true;
 }
 
-void ColumnLowCardinality::Dictionary::compact(ColumnPtr & positions)
+void ColumnLowCardinality::Dictionary::compact(MutableColumnPtr & positions)
 {
-    auto new_column_unique = column_unique->cloneEmpty();
+    column_unique = compact(getColumnUnique(), positions);
+    shared = false;
+}
 
-    auto & unique = getColumnUnique();
+MutableColumnPtr ColumnLowCardinality::Dictionary::compact(const IColumnUnique & unique, MutableColumnPtr & positions)
+{
+    auto new_column_unique = unique.cloneEmpty();
     auto & new_unique = static_cast<IColumnUnique &>(*new_column_unique);
 
-    auto indexes = mapUniqueIndex(positions->assumeMutableRef());
+    auto indexes = mapUniqueIndex(*positions);
     auto sub_keys = unique.getNestedColumn()->index(*indexes, 0);
     auto new_indexes = new_unique.uniqueInsertRangeFrom(*sub_keys, 0, sub_keys->size());
 
     positions = IColumn::mutate(new_indexes->index(*positions, 0));
-    column_unique = std::move(new_column_unique);
-
-    shared = false;
+    return new_column_unique;
 }
 
 ColumnPtr ColumnLowCardinality::cloneWithDefaultOnNull() const
diff --git a/src/Columns/ColumnLowCardinality.h b/src/Columns/ColumnLowCardinality.h
index f9bf7290601..a5c056153bb 100644
--- a/src/Columns/ColumnLowCardinality.h
+++ b/src/Columns/ColumnLowCardinality.h
@@ -303,8 +303,8 @@ public:
 
         void checkSizeOfType();
 
-        ColumnPtr detachPositions() { return std::move(positions); }
-        void attachPositions(ColumnPtr positions_);
+        MutableColumnPtr detachPositions() { return IColumn::mutate(std::move(positions)); }
+        void attachPositions(MutableColumnPtr positions_);
 
         void countKeys(ColumnUInt64::Container & counts) const;
 
@@ -352,7 +352,9 @@ private:
         bool isShared() const { return shared; }
 
         /// Create new dictionary with only keys that are mentioned in positions.
-        void compact(ColumnPtr & positions);
+        void compact(MutableColumnPtr & positions);
+
+        static MutableColumnPtr compact(const IColumnUnique & column_unique, MutableColumnPtr & positions);
 
     private:
         WrappedPtr column_unique;