(PHP 5, PHP 7, PECL OCI8 >= 1.1.0)
oci_set_prefetch — 锟斤拷锟斤拷预锟斤拷取锟斤拷锟斤拷
$statement
[, int $rows
] ) : bool
锟节成癸拷锟斤拷锟斤拷 oci_execute()
之锟斤拷锟借定预锟斤拷取锟斤拷锟斤拷锟斤拷锟斤拷rows 锟斤拷默锟斤拷值为 1锟斤拷
Note:
锟斤拷 PHP 5.0.0 之前锟侥版本锟斤拷锟斤拷使锟斤拷 ocisetprefetch() 锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷煤锟斤拷锟斤拷锟斤拷锟饺伙拷锟斤拷茫锟轿拷锟斤拷录锟斤拷锟斤拷锟轿� oci_set_prefetch() 锟侥憋拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟窖憋拷锟斤拷锟斤拷锟斤拷锟斤拷锟狡硷拷使锟矫★拷
锟缴癸拷时锟斤拷锟斤拷 TRUE锟斤拷 锟斤拷锟斤拷锟斤拷失锟斤拷时锟斤拷锟斤拷 FALSE锟斤拷
锟轿硷拷 oci8_.default_prefetch INI 选锟筋。
statement锟斤拷效锟斤拷 OCI8 锟斤拷锟斤拷锟绞讹拷锟� 锟斤拷 oci_parse() 锟斤拷锟斤拷锟斤拷锟斤拷 oci_execute() 锟斤拷 REF CURSOR statement 锟斤拷识执锟叫★拷
rowsThe number of rows to be prefetched, >= 0
锟缴癸拷时锟斤拷锟斤拷 TRUE锟斤拷 锟斤拷锟斤拷锟斤拷失锟斤拷时锟斤拷锟斤拷 FALSE锟斤拷
| 锟芥本 | 说锟斤拷 |
|---|---|
| PHP 5.3.2 (PECL OCI8 1.4) |
Before this release, rows must be >= 1.
|
| PHP 5.3 (PECL OCI8 1.3.4) |
Before this release, prefetching was limited to the lesser
of rows rows and 1024
* rows bytes. The byte size
restriction has now been removed.
|
Example #1 Changing the default prefetch value for a query
<?php
$conn = oci_connect('hr', 'welcome', 'localhost/XE');
$stid = oci_parse($conn, 'SELECT * FROM myverybigtable');
oci_set_prefetch($stid, 300); // Set before calling oci_execute()
oci_execute($stid);
echo "<table border='1'>\n";
while ($row = oci_fetch_array($stid, OCI_ASSOC+OCI_RETURN_NULLS)) {
echo "<tr>\n";
foreach ($row as $item) {
echo " <td>".($item !== null ? htmlentities($item, ENT_QUOTES) : " ")."</td>\n";
}
echo "</tr>\n";
}
echo "</table>\n";
oci_free_statement($stid);
oci_close($conn);
?>
Example #2 Changing the default prefetch for a REF CURSOR fetch
<?php
/*
Create the PL/SQL stored procedure as:
CREATE OR REPLACE PROCEDURE myproc(p1 OUT SYS_REFCURSOR) AS
BEGIN
OPEN p1 FOR SELECT * FROM all_objects WHERE ROWNUM < 5000;
END;
*/
$conn = oci_connect('hr', 'welcome', 'localhost/XE');
$stid = oci_parse($conn, 'BEGIN myproc(:rc); END;');
$refcur = oci_new_cursor($conn);
oci_bind_by_name($stid, ':rc', $refcur, -1, OCI_B_CURSOR);
oci_execute($stid);
// Change the prefetch before executing the cursor.
// REF CURSOR prefetching works when PHP is linked with Oracle 11gR2 Client libraries
oci_set_prefetch($refcur, 200);
oci_execute($refcur);
echo "<table border='1'>\n";
while ($row = oci_fetch_array($refcur, OCI_ASSOC+OCI_RETURN_NULLS)) {
echo "<tr>\n";
foreach ($row as $item) {
echo " <td>".($item !== null ? htmlentities($item, ENT_QUOTES) : " ")."</td>\n";
}
echo "</tr>\n";
}
echo "</table>\n";
oci_free_statement($refcur);
oci_free_statement($stid);
oci_close($conn);
?>
If PHP OCI8 fetches from a REF CURSOR and then passes the REF
CURSOR back to a second PL/SQL procedure for further processing,
then set the REF CURSOR prefetch count to 0 to
avoid rows being "lost" from the result set. The prefetch value is
the number of extra rows fetched in each OCI8 internal request to
the database, so setting it to 0 means only
fetch one row at a time.
Example #3 Setting the prefetch value when passing a REF CURSOR back to Oracle
<?php
$conn = oci_connect('hr', 'welcome', 'localhost/orcl');
// get the REF CURSOR
$stid = oci_parse($conn, 'BEGIN myproc(:rc_out); END;');
$refcur = oci_new_cursor($conn);
oci_bind_by_name($stid, ':rc_out', $refcur, -1, OCI_B_CURSOR);
oci_execute($stid);
// Display two rows, but don't prefetch any extra rows otherwise
// those extra rows would not be passed back to myproc_use_rc().
// A prefetch value of 0 is allowed in PHP 5.3.2 and PECL OCI8 1.4
oci_set_prefetch($refcur, 0);
oci_execute($refcur);
$row = oci_fetch_array($refcur);
var_dump($row);
$row = oci_fetch_array($refcur);
var_dump($row);
// pass the REF CURSOR to myproc_use_rc() to do more data processing
// with the result set
$stid = oci_parse($conn, 'begin myproc_use_rc(:rc_in); end;');
oci_bind_by_name($stid, ':rc_in', $refcur, -1, OCI_B_CURSOR);
oci_execute($stid);
?>
Note:
In PHP versions before 5.0.0 use ocisetprefetch() instead. 锟节碉拷前锟芥本锟叫ｏ拷锟缴的猴拷锟斤拷锟斤拷锟斤拷锟斤拷锟皆憋拷使锟矫ｏ拷锟斤拷锟窖撅拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷使锟矫★拷