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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}
        if (type->haveMaximumSizeOfValue() && (!best_size || type->getSizeOfValueInMemory() < best_size))
        {
            if (which.isInt8() || which.isUInt8())
            {
                best_size = type->getSizeOfValueInMemory();
                best_partition = std::make_shared<ASTIdentifier>(primary_key.name);
                if (primary_key.type->isNullable())
                    best_partition = makeASTFunction("assumeNotNull", best_partition);
            }
            else if (which.isInt16() || which.isUInt16())
            {
                best_size = type->getSizeOfValueInMemory();
                best_partition = numbers_partition(primary_key.name, primary_key.type->isNullable(), std::numeric_limits<UInt16>::max());
            }
            else if (which.isInt32() || which.isUInt32())
            {
                best_size = type->getSizeOfValueInMemory();
                best_partition = numbers_partition(primary_key.name, primary_key.type->isNullable(), std::numeric_limits<UInt32>::max());
            }
            else if (which.isInt64() || which.isUInt64())
            {
                best_size = type->getSizeOfValueInMemory();
                best_partition = numbers_partition(primary_key.name, primary_key.type->isNullable(), std::numeric_limits<UInt64>::max());
            }
        }
    }
    return best_partition;
}
static ASTPtr getOrderByPolicy(