```sql
create table dat (blockNum Decimal(10,0), eventTimestamp DateTime64(9) ) 
Engine=MergeTree() primary key eventTimestamp;
insert into dat values (1, '2022-01-24 02:30:00.008122000');

CREATE DICTIONARY datDictionary
(
    `blockNum` Decimal(10, 0),
    `eventTimestamp` DateTime64(9)
)
PRIMARY KEY blockNum
SOURCE(CLICKHOUSE(TABLE 'dat'))
LIFETIME(MIN 0 MAX 1000)
LAYOUT(FLAT());

select * from datDictionary;
┌─blockNum─┬────────────────eventTimestamp─┐
│        1 │ 2022-01-24 02:30:00.008122000 │
└──────────┴───────────────────────────────┘

select count(*) from dat where eventTimestamp >= (select eventTimestamp from datDictionary);

Exception on client:
Code: 32. DB::Exception: Attempt to read after eof: while receiving packet from localhost:9000. (ATTEMPT_TO_READ_AFTER_EOF)

Connecting to localhost:9000 as user default.
Code: 210. DB::NetException: Connection refused (localhost:9000). (NETWORK_ERROR)
```

```sql
drop dictionary datDictionary;

CREATE DICTIONARY datDictionary
(
    `blockNum` Decimal(10, 0),
    `eventTimestamp` DateTime64(9)
)
PRIMARY KEY blockNum
SOURCE(CLICKHOUSE(TABLE 'dat'))
LIFETIME(MIN 0 MAX 1000)
LAYOUT(complex_key_hashed());

select count(*) from dat where eventTimestamp >= (select eventTimestamp from datDictionary);

Error on processing query: Code: 32. DB::Exception: Attempt to read after eof: while receiving packet from localhost:9000. (ATTEMPT_TO_READ_AFTER_EOF) (version 22.7.1.1054)

Connecting to localhost:9000 as user default.
Code: 210. DB::NetException: Connection refused (localhost:9000). (NETWORK_ERROR)
```

```sql
select * from datDictionary;
┌─blockNum─┬────────────────eventTimestamp─┐
│        1 │ 2022-01-24 02:30:00.008122000 │
└──────────┴───────────────────────────────┘

select dictGet('datDictionary', 'eventTimestamp', tuple(cast('1','Decimal(10,0)')));
Code: 407. DB::Exception: Received from localhost:9000. DB::Exception: Bad scale of decimal field. (DECIMAL_OVERFLOW)
```

{
            if (const DataTypeNullable * type_nullable = typeid_cast<const DataTypeNullable *>(type.get()))
            {
                have_nullable = true;
                if (!type_nullable->onlyNull())
                    nested_types.emplace_back(type_nullable->getNestedType());
            }
            else
                nested_types.emplace_back(type);
        }
        if (have_nullable)
        {
            auto nested_type = getLeastSupertype<on_error>(nested_types);
            
            
            if (!nested_type)
                return nullptr;
            return std::make_shared<DataTypeNullable>(nested_type);
        }
    }
    
    TypeIndexSet type_ids;
    for (const auto & type : types)
        type_ids.insert(type->getTypeId());
    
    
    {
        UInt32 have_string = type_ids.count(TypeIndex::String);
        UInt32 have_fixed_string = type_ids.count(TypeIndex::FixedString);
        if (have_string || have_fixed_string)