Method processQuery

src/Server/PostgreSQLHandler.cpp:585–671

}

void PostgreSQLHandler::processQuery()
{
    try
    {
        std::unique_ptr<PostgreSQLProtocol::Messaging::Query> query =
            message_transport->receive<PostgreSQLProtocol::Messaging::Query>();

        if (isEmptyQuery(query->query))
        {
            message_transport->send(PostgreSQLProtocol::Messaging::EmptyQueryResponse());
            return;
        }

        bool psycopg2_cond = query->query == "BEGIN" || query->query == "COMMIT"; // psycopg2 starts and ends queries with BEGIN/COMMIT commands
        bool jdbc_cond = query->query.contains("SET extra_float_digits") || query->query.contains("SET application_name"); // jdbc starts with setting this parameter
        if (psycopg2_cond || jdbc_cond)
        {
            message_transport->send(
                PostgreSQLProtocol::Messaging::CommandComplete(
                    PostgreSQLProtocol::Messaging::CommandComplete::classifyQuery(query->query), 0));
            return;
        }

        const auto & settings = session->sessionContext()->getSettingsRef();
        std::vector<String> queries;

        if (processPrepareStatement(query->query))
            return;

        if (processDeallocate(query->query))
            return;

        if (processCopyQuery(query->query))
            return;

        pcg64_fast gen{randomSeed()};
        std::uniform_int_distribution<Int32> dis(0, INT32_MAX);

        secret_key = dis(gen);
        auto query_context = session->makeQueryContext();
        query_context->setCurrentQueryId(fmt::format("postgres:{:d}:{:d}", connection_id, secret_key));

        if (should_init_system_tables)
        {
            initializeSystemTables(query_context);
            should_init_system_tables = false;
        }

        if (processExecute(query->query, query_context))
            return;

        auto parse_res = splitMultipartQuery(
            query->query,
            queries,
            settings[Setting::max_query_size],
            settings[Setting::max_parser_depth],
            settings[Setting::max_parser_backtracks],
            settings[Setting::allow_settings_after_format_in_insert],