(PHP 4, PHP 5, PHP 7, PHP 8)
pg_fetch_object — Carica una tupla in un oggetto
pg_fetch_object() restituisce un oggetto avente
le proprietà che corrispondono alla tupla scaricata. Restituisce false
se non ci sono più tuple o in caso di errore.
pg_fetch_object() è simile a pg_fetch_array(), con una differenza - viene restituito un oggetto invece che un array. Indirettamente, questo significa che si può accedere ai dati solo attraverso i nomi dei campi, e non attraverso i loro indici numerici (i nomi delle proprietà non possono essere numeri).
tupla è il numero della riga (record) da
caricare. La prima tupla è la numero 0.
Per quanto riguarda la velocità di esecuzione, questa funzione è identica a pg_fetch_array(), ed è veloce quasi quanto pg_fetch_row() (la differenza è trascurabile).
Nota:
Dalla versione 4.1.0,
tuplaè opzionale.Dalla versione 4.3.0,
tipo_risultatoè di default a PGSQL_ASSOC mentre il default delle versioni precedenti era PGSQL_BOTH. La proprietà numerica è inutile, dal momento che un nome di proprietà numerico non è valido in PHP.
tipo_risultatopotrebbe essere abbandonato nelle versioni future.
Example #1 Postgres fetch object
<?php
$database = "verlag";
$db_conn = pg_connect ("host=localhost port=5432 dbname=$database");
if (!$db_conn): ?>
<H1>Failed connecting to postgres database <?php echo $database ?></H1> <?php
exit;
endif;
$qu = pg_exec ($db_conn, "SELECT * FROM verlag ORDER BY autor");
$row = 0; // postgres needs a row counter other dbs might not
while ($data = pg_fetch_object ($qu, $row)) {
echo $data->autor." (";
echo $data->jahr ."): ";
echo $data->titel."<BR>";
$row++;
}
?>
<PRE>
<?php
$fields[] = Array ("autor", "Author");
$fields[] = Array ("jahr", " Year");
$fields[] = Array ("titel", " Title");
$row= 0; // postgres needs a row counter other dbs might not
while ($data = pg_fetch_object ($qu, $row)) {
echo "----------\n";
reset ($fields);
while (list (,$item) = each ($fields)):
echo $item[1].": ".$data->$item[0]."\n";
endwhile;
$row++;
}
echo "----------\n";
?>
</PRE>
<?php
pg_freeresult ($qu);
pg_close ($db_conn);
?>Vedere anche pg_query(), pg_fetch_array(), pg_fetch_row() e pg_fetch_result().
Nota:
Dalla versione 4.1.0,
rowè diventato opzionale. La chiamata alla pg_fetch_object() incrementa di 1 il contatore di riga interno.
PostgreSQL boolean true becomes string "t"
PostgreSQL boolean false becomes string "f"
This is ambiguous, and leads to code duplication. I wonder why aren't the types correctly typed when fetching values. We could at least have an optional parameter to enable that.If you're wanting to use objects for your results, but are put off because you can't seem to apply a function to each field of the result (like stripslashes for example), try this code:
<?php
// Code to connect, do query etc etc...
$row = pg_fetch_object($result);
$vars = get_object_vars($row);
foreach ( $vars as $key => $var )
{
$row->{$key} = stripslashes($var);
}
?>I noticed that many people use FOR loops to extract query data. This is the method I use to extract data.
<?php
@$members = pg_query($db_conn, 'SELECT id,name FROM boards.members ORDER BY name;');
if ($members AND pg_num_rows($members)) {
while ($member = pg_fetch_object($members)) {
echo $member->name.' ('.$member->id.')';
}
}
?>
If an error occurs (or nothing is returned) in the above code nothing will output. An ELSE clause can be added to the IF to handle query errors (or nothing being returned). Or a seperate check can be performed for the event that nothing is returned by using an ELSEIF clause.
I like this method because it doesn't use any temporary counter variables.The result_type arg is either invalid or incorrectly documented, since the "result_type is optional..." paragraph is copied verbatim from pg_fetch_array, and the PGSQL_NUM option is in conflict with the preceding paragraph's, "you can only access the data by the field names, and not by their
offsets."When you retrieve the contents of a "timestamp with timezone" field, this will set the environment's timezone variables. Therefore, this is dangerous:
$s=$row->mydatefield;
$unixtimestamp=postgresqltimestamp2unix($s);
echo date("Y-m-d H:i:s",$unixtimestamp);
Here, postgresqltimestamp2unix is a function that converts the postgresql timestamp to Unix. The retrieval of the field data in the first line of the example above will influence the timezone used in date() in the third line.This isn't all that useful. If you do, for example, foreach($row as $field) then you still get every value twice!
You can do something like this, though:
foreach ($line as $key => $cell){
if (! is_numeric($key)){
echo "<td>$key $cell</td>";
}
}
is is_numeric strict enough?Getting db results as object.
<?php
$qry = pg_query("SELECT * FROM users");
$rows = array();
while ($fch = pg_fetch_object($qry)) {
$rows[] = $fch;
}
// or
$rows = array_map(function($a){
return (object) $a;
}, (array) pg_fetch_all($qry));
?>Something I have learned to use:
$result=$pg_query (...);
$num = pg_numrows($result);
for($count=0;$count < $num && $data=pg_fetch_object($result,$count);$count++)
{
printf("<tr>\n");
printf(" <td>%s</td>\n",$data->foo);
printf(" <td>%s</td>\n",$data->bar);
printf("</tr>\n");
}