There is no way to poll/wait for a notification to come in. You either have to enter a busy loop or sleep. Both options are horrible. It would be nice for PHP to provide access to PQsocket so one could select() on the socket connection. This is how it's done from C or Perl.pg_get_result
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pg_get_result
Референца за `function.pg-get-result.php` со подобрена типографија и навигација.
pg_get_result
(PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8)
pg_get_result — Добијте резултат од асинхронизирано барање
= NULL
pg_get_result() добива PgSql\Result инстанца од асинхронизирано барање извршено од pg_send_query(), pg_send_query_params() or pg_send_execute().
pg_send_query() и другите функции за асинхронизирано барање можат да испратат повеќе барања до PostgreSQL сервер и pg_get_result() се користи за добивање на резултатите од секое барање, едно по едно.
Вратени вредности
Еден PgSql\Result инстанца, или false ако нема повеќе достапни резултати.
Дневник на промени
| Верзија | = NULL |
|---|---|
| 8.1.0 | Враќа PgSql\Result инстанца сега; претходно, а resource . |
| 8.1.0 |
На connection параметарот очекува PgSql\Connection
инстанца сега; претходно, а resource се очекуваше.
|
Примери
Пример #1 pg_get_result() example
<?php
$dbconn = pg_connect("dbname=publisher") or die("Could not connect");
if (!pg_connection_busy($dbconn)) {
pg_send_query($dbconn, "select * from authors; select count(*) from authors;");
}
$res1 = pg_get_result($dbconn);
echo "First call to pg_get_result(): $res1\n";
$rows1 = pg_num_rows($res1);
echo "$res1 has $rows1 records\n\n";
$res2 = pg_get_result($dbconn);
echo "Second call to pg_get_result(): $res2\n";
$rows2 = pg_num_rows($res2);
echo "$res2 has $rows2 records\n";
?>Пример #1 Пример што покажува затворачка ознака што го опфаќа последниот нов ред
First call to pg_get_result(): Resource id #3 Resource id #3 has 3 records Second call to pg_get_result(): Resource id #4 Resource id #4 has 1 records
Белешки од корисници 4 белешки
It might seem that after calling pg_get_result() upon sending just a single query, the connection will not be busy. The correct way is, though, to call extra pg_get_result() in a loop until it returns false [1].
<?php
$conn = pg_connect('...', PGSQL_CONNECT_FORCE_NEW);
for ($i = 0; $i < 10000; $i++) {
$query = 'erroneous query';
if (pg_connection_busy($conn)) {
fprintf(STDERR, "Connection is busy\n");
exit(1);
}
pg_send_query($conn, $query);
$res = pg_get_result($conn);
if ($res === false) {
fprintf(STDERR, "A result was expected\n");
exit(1);
}
/* The following does not seem necessary for good queries, but is vital for erroneous queries.
Commenting the loop out leads to this script fail with the "Connection is busy" error. */
while (pg_get_result($conn));
// result processing...
}
?>
See http://www.postgresql.org/message-id/flat/[email protected]#[email protected] and https://bugs.php.net/bug.php?id=52750 for detailed information.
[1] Or, even better, use an asynchronous connection since PHP 5.6.To have a a simple wait output with async queries you can use the pg_connection_busy command:
<?php
$dbh = pg_connect("host=XXX user=XXX password=XXX dbname=XXX");
if (!$dbh)
{
print "Failed to connect";
exit;
}
$query = "SELECT pg_sleep(10)";
if (!pg_connection_busy($dbh))
{
$sent = pg_send_query($dbh, $query);
print "Sent query, waiting: ";
while (pg_connection_busy($dbh)
{
print ".";
flush();
}
$res = pg_get_result($dbh);
print "<br>"; // or \n
print "Result is: $res";
}
pg_close($dbh);
?>william at 25thandClement dot com said: "There is no way to poll/wait for a notification to come in. .."
Yes, there is. If there is a query in progress, pg_get_result() will block and return the result of that query when it's complete.