message: Use the correct storage type for column keys
diff: @@ -32,7 +32,7 @@ namespace _impl {
  class ObjectChangeSet {
  public:
  - using ColKeyType = uint64_t;
  + using ColKeyType = int64_t;
  using ObjectKeyType = int64_t;
  using ObjectSet = std::unordered_set<ObjectKeyType>;
  using ObjectMapToColumnSet = std::unordered_map<ObjectKeyType, std::unordered_set<ColKeyType>>;
  