**How to reproduce**
Clickhouse version 21.5

```
cat /etc/clickhouse-server/users.xml
<?xml version="1.0"?>
<yandex>
    <!-- Profiles of settings. -->
    <profiles>
        <!-- Default settings. -->
        <default>
            <data_type_default_nullable>1</data_type_default_nullable>
            <load_balancing>random</load_balancing>
        </default>
....

2021.04.04 01:23:42.453678 [ 29048 ] {} <Error> Application: DB::Exception: Nested type Array(UInt64) cannot be inside Nullable type: Cannot attach table `system`.`crash_log` from metadata file /var/lib/clickhouse/metadata/system/crash_log.sql from query ATTACH TABLE system.crash_log (`event_date` Date, `event_time` DateTime, `timestamp_ns` UInt64, `signal` Int32, `thread_id` UInt64, `query_id` String, `trace` Array(UInt64), `trace_full` Array(String), `version` String, `revision` UInt32, `build_id` String) ENGINE = MergeTree ORDER BY (event_date, event_time) SETTINGS index_granularity = 8192: while loading database `system` from path /var/lib/clickhouse/metadata/system
```
{
    if (create.as_table_function)
        return;
    if (create.storage || create.is_dictionary || create.isView())
    {
        if (create.temporary && create.storage && create.storage->engine && create.storage->engine->name != "Memory")
            throw Exception(
                "Temporary tables can only be created with ENGINE = Memory, not " + create.storage->engine->name,
                ErrorCodes::INCORRECT_QUERY);
        return;
    }
    if (create.temporary)
    {
        auto engine_ast = std::make_shared<ASTFunction>();
        engine_ast->name = "Memory";
        engine_ast->no_empty_args = true;
        auto storage_ast = std::make_shared<ASTStorage>();
        storage_ast->set(storage_ast->engine, engine_ast);
        create.set(create.storage, storage_ast);
    }
    else if (!create.as_table.empty())
    {
        
        String as_database_name = getContext()->resolveDatabase(create.as_database);
        String as_table_name = create.as_table;
        ASTPtr as_create_ptr = DatabaseCatalog::instance().getDatabase(as_database_name)->getCreateTableQuery(as_table_name, getContext());
        const auto & as_create = as_create_ptr->as<ASTCreateQuery &>();
        const String qualified_name = backQuoteIfNeed(as_database_name) + "." + backQuoteIfNeed(as_table_name);
        if (as_create.is_ordinary_view)
            throw Exception(