Reintroduce compatibility with is_deleted on a syntax level

src/Storages/MergeTree/registerStorageMergeTree.cpp

@@ -441,6 +441,15 @@ static StoragePtr create(const StorageFactory::Arguments & args)
  }
  else if (merging_params.mode == MergeTreeData::MergingParams::Replacing)
  {
+ /// Due to a misfortune, there could be an extra obsolete parameter.
+ /// We ignore it for backward compatibility.
+ if (arg_cnt - arg_num == 2 && !engine_args[arg_cnt - 1]->as<ASTLiteral>() && is_extended_storage_def)
+ {
+ if (!tryGetIdentifierName(engine_args[arg_cnt - 1]))
+ throw Exception(ErrorCodes::BAD_ARGUMENTS, "is_deleted column name must be an identifier {}", verbose_help_message);
+ --arg_cnt;
+ }
+
  /// If the last element is not index_granularity or replica_name (a literal), then this is the name of the version column.
  if (arg_cnt && !engine_args[arg_cnt - 1]->as<ASTLiteral>())
  {