Method receiveSampleBlock

src/Client/ClientBase.cpp:1892–1926

Receive the block that serves as an example of the structure of table where data will be inserted.

/// Receive the block that serves as an example of the structure of table where data will be inserted.
bool ClientBase::receiveSampleBlock(Block & out, ColumnsDescription & columns_description, ASTPtr parsed_query)
{
    while (true)
    {
        Packet packet = connection->receivePacket();

        switch (packet.type)
        {
            case Protocol::Server::Data:
                out = packet.block;
                return true;

            case Protocol::Server::Exception:
                onReceiveExceptionFromServer(std::move(packet.exception));
                return false;

            case Protocol::Server::Log:
                onLogData(packet.block);
                break;

            case Protocol::Server::TableColumns:
                columns_description = ColumnsDescription::parse(packet.columns_description);
                return receiveSampleBlock(out, columns_description, parsed_query);

            case Protocol::Server::TimezoneUpdate:
                onTimezoneUpdate(packet.server_timezone);
                break;

            default:
                throw NetException(ErrorCodes::UNEXPECTED_PACKET_FROM_SERVER,
                    "Unexpected packet from server (expected Data, Exception, Log or TimezoneUpdate, got {})",
                    String(Protocol::Server::toString(packet.type)));
        }
    }
}


void ClientBase::setInsertionTable(const ASTInsertQuery & insert_query)