i use
my steps
1. create a new database ckdb on mysql, then  create table t1(a int, primary key(a)); and insert some rows
2. SET allow_experimental_database_materialize_mysql=1; at clickhouse, 
3. CREATE DATABASE ckdb ENGINE = MaterializeMySQL('127.0.0.1:3306', 'ckdb', 'root', 'A123b_456');
4. use ckdb and select * from t1 ok
5. create table dzm as select * from others in mysql ----> cannot see dzm in clickhouse, but if select * from t1, reports
```
Code: 48. DB::Exception: Received from localhost:9000. DB::Exception: The ckdb.dzm cannot be materialized, because there is no primary keys..
```
6. create table t2(a int,b int primary a);----> cannot see t2 in clickhouse, , but if select * from t1, reports
```
Code: 44. DB::Exception: Received from localhost:9000. DB::Exception: Sorting key cannot contain nullable columns.
```
<del>7. if i drop ckdb and recreate it, all tables can be selected </del>
7.if there are some 'bad' tables in a database, all tables in that database cannot be selected

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keys->arguments->children.insert(keys->arguments->children.end(),
                    declare_index->index_columns->children.begin(), declare_index->index_columns->children.end());
            else if (startsWith(declare_index->index_type, "UNIQUE_"))
                unique_keys->arguments->children.insert(keys->arguments->children.end(),
                    declare_index->index_columns->children.begin(), declare_index->index_columns->children.end());
            if (startsWith(declare_index->index_type, "PRIMARY_KEY_"))
                primary_keys->arguments->children.insert(keys->arguments->children.end(),
                    declare_index->index_columns->children.begin(), declare_index->index_columns->children.end());
        }
    }
    for (const auto & declare_column_ast : columns_define->children)
    {
        const auto & declare_column = declare_column_ast->as<MySQLParser::ASTDeclareColumn>();
        if (declare_column->column_options)
        {
            if (const auto * options = declare_column->column_options->as<MySQLParser::ASTDeclareOptions>())
            {
                if (options->changes.count("unique_key"))
                    unique_keys->arguments->children.emplace_back(std::make_shared<ASTIdentifier>(declare_column->name));
                if (options->changes.count("primary_key"))
                    primary_keys->arguments->children.emplace_back(std::make_shared<ASTIdentifier>(declare_column->name));
                if (options->changes.count("auto_increment"))
                    increment_columns.emplace(declare_column->name);
            }
        }
    }
    return std::make_tuple(
        getNames(*primary_keys, context, columns), getNames(*unique_keys, context, columns), getNames(*keys, context, columns), increment_columns);
}
static String getUniqueColumnName(NamesAndTypesList columns_name_and_type, const String & prefix)