```sql
CREATE TABLE t
(
   id Int64, 
   d String,
   p Map(String, String)
   
)
ENGINE = ReplacingMergeTree order by id settings index_granularity  = 0;


insert into t values (1,  's', {'a':'b'});

CH starts eating RAM until it crashes

the same with

insert into t select 1,  's', map('a','b');

```

throw Exception(
                    "Trying to ALTER DROP key " + backQuoteIfNeed(command.column_name) + " column which is a part of key expression",
                    ErrorCodes::ALTER_OF_COLUMN_IS_FORBIDDEN);
            }
            if (!command.clear)
            {
                const auto & deps_mv = name_deps[command.column_name];
                if (!deps_mv.empty())
                {
                    throw Exception(
                        "Trying to ALTER DROP column " + backQuoteIfNeed(command.column_name) + " which is referenced by materialized view "
                            + toString(deps_mv),
                        ErrorCodes::ALTER_OF_COLUMN_IS_FORBIDDEN);
                }
            }
            if (old_metadata.columns.has(command.column_name))
            {
                dropped_columns.emplace(command.column_name);
            }
            else
            {
                const auto & nested = old_metadata.columns.getNested(command.column_name);
                for (const auto & nested_column : nested)
                    dropped_columns.emplace(nested_column.name);
            }
        }
        else if (command.type == AlterCommand::RESET_SETTING)
        {
            for (const auto & reset_setting : command.settings_resets)
            {