```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 (have_datetime == 0 && have_datetime64 == 0)
            {
                for (const auto & type : types)
                {
                    if (isDate32(type))
                        return type;
                }
            }
            
            if (have_datetime == 1 && have_date32 == 1 && have_datetime64 == 0)
            {
                return std::make_shared<DataTypeDateTime64>(0);
            }
            UInt8 max_scale = 0;
            size_t max_scale_date_time_index = 0;
            for (size_t i = 0; i < types.size(); ++i)
            {
                const auto & type = types[i];
                if (const auto * date_time64_type = typeid_cast<const DataTypeDateTime64 *>(type.get()))
                {
                    const auto scale = date_time64_type->getScale();
                    if (scale >= max_scale)
                    {
                        max_scale_date_time_index = i;
                        max_scale = scale;
                    }
                }
            }
            return types[max_scale_date_time_index];
        }