message: Rename a couple of unused variables from `dummy` to `unused`.
diff: @@ -543,8 +543,8 @@ void IndexArray::index_string_all_ins(StringData value, IntegerColumn& result, C
  size_t IndexArray::index_string_find_first(StringData value, ColumnBase* column) const
  {
  - InternalFindResult dummy;
  - return index_string<index_FindFirst>(value, dummy, column);
  + InternalFindResult unused;
  + return index_string<index_FindFirst>(value, unused, column);
  }
  @@ -565,8 +565,8 @@ FindRes IndexArray::index_string_find_all_no_copy(StringData value, ColumnBase*
  size_t IndexArray::index_string_count(StringData value, ColumnBase* column) const
  {
  - InternalFindResult dummy2;
  - return index_string<index_Count>(value, dummy2, column);
  + InternalFindResult unused;
  + return index_string<index_Count>(value, unused, column);
  }
  IndexArray* StringIndex::create_node(Allocator& alloc, bool is_leaf)
  