Strange behavior with dateTime

I modified example

inline void DateTime64Example(Client& client) { Block b;

/// Create a table.
client.Execute("CREATE  TABLE IF NOT EXISTS test_datetime64 (dt64 DateTime64(6) primary key)");

std::cerr << std::endl;
{
    Query query("insert into test_datetime64 values('2024-10-10 11:00:00')");
    client.Execute(query);
}
{
    Query query("insert into test_datetime64 FORMAT TSV \n2024-10-10 11:01:00");
    client.Execute(query);
}
auto d = std::make_shared<ColumnDateTime64>(6);
std::time_t tt = std::time(nullptr);
std::cerr << "inserted local time: " << std::asctime(std::localtime(&tt));
std::cerr << "inserted utc: " << std::asctime(std::gmtime(&tt));
d->Append(tt * (int64_t)1000000 + 123456);

b.AppendColumn("dt64", d);
client.Insert("test_datetime64", b);

client.Select("SELECT dt64 FROM test_datetime64 format tsv", [](const Block& block)
    {
        for (size_t c = 0; c < block.GetRowCount(); ++c) {
            auto col = block[0]->As<ColumnDateTime64>();
            uint64_t t = col->As<ColumnDateTime64>()->At(c);

            std::time_t ct = t / 1000000;
            uint64_t us = t % 1000000;
            std::cerr << "selected local time: " << std::asctime(std::localtime(&ct));
            std::cerr << "selected utc time: " << std::asctime(std::gmtime(&ct));
            std::cerr << "us: " << us << std::endl;
        }
    }
);

/// Delete table.

// client.Execute("DROP TEMPORARY TABLE test_datetime64"); }

The server was run with time zone Asia/Tokyo. The test program I run twice in two different time zones Europe/Paris Europe/Moscow and has the results of insert:

selected local time: Thu Oct 10 05:00:00 2024 selected utc time: Thu Oct 10 02:00:00 2024 us: 0 selected local time: Thu Oct 10 05:00:00 2024 selected utc time: Thu Oct 10 02:00:00 2024 us: 0 selected local time: Thu Oct 10 05:01:00 2024 selected utc time: Thu Oct 10 02:01:00 2024 us: 0 selected local time: Thu Oct 10 05:01:00 2024 selected utc time: Thu Oct 10 02:01:00 2024 us: 0 selected local time: Thu Oct 10 11:32:57 2024 selected utc time: Thu Oct 10 08:32:57 2024 us: 123456 selected local time: Thu Oct 10 11:33:09 2024 selected utc time: Thu Oct 10 08:33:09 2024 us: 123456 I see that text query (value or TSV format) inserted data in server time zone. Data that inserted via Client.Insert() has utc time zone. Time zone of text insert and time zone of binary insert is different! I need unification of time working.

Also will be very good if I can insert data in client local time zone. I did not found way to insert time in client time zone in text formats.

There is output of the client: SELECT * FROM test_datetime64

Query id: 560fd02a-cb6c-4303-8947-2c9727cd1793

┌───────────────────────dt64─┐

│ 2024-10-10 17:33:09.123456 │ └────────────────────────────┘ ┌───────────────────────dt64─┐
│ 2024-10-10 11:00:00.000000 │
│ 2024-10-10 11:00:00.000000 │
│ 2024-10-10 11:01:00.000000 │
│ 2024-10-10 11:01:00.000000 │
│ 2024-10-10 17:32:57.123456 │ └────────────────────────────┘

ClickHouse / clickhouse-cpp

Strange behavior with dateTime #398