[iliaal]

closeCursor() clears stmt->executed, so the next execute() reallocates S->cols while PDO core keeps its column descriptions and never describes them again; the OCI defines keep writing into the freed buffers and the next fetch crashes. Dropping PDO's descriptions with php_pdo_stmt_set_column_count(stmt, 0), as pdo_sqlsrv does, makes core describe the columns into the new buffers. PHP 8.4.27RC1, 8.5.12RC1 and 8.6.0RC3 reach the same branch on every re-execute (#44, php/php-src#24372), so this covers that too; the core side is fixed separately.

[iliaal]

The 8.4/8.5/master failures are the php-src common PDO tests run from the branch head against the released setup-php binary (8.5.11 here); those tests assert fixes newer than that release, so main fails the same way. The new test passes on all lanes.

[m3ct0n]

Thanks for this. With this branch on PHP 8.4.27 the SELECT crash is gone for us (Debian 13, Instant Client 19.12, Oracle 11.2.0.4), but re-executing a non-query statement still fails.

pdo_oci has no cursor_closer, so on 8.4.27 / 8.5.12 PDO drains the previous result through the fetcher before every re-execute. That calls OCIStmtFetch2() on DML / DDL handles too, and the next OCIStmtExecute() fails:

$st = $dbh->prepare("ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS'");
$st->execute();
$st->execute(); // ORA-01002: fetch out of sequence

yiisoft/yii2#21122 reports ORA-03137 for a re-executed UPDATE, same cause.

Would you consider adding a cursor closer that cancels the cursor of a query only, with the same zero-row fetch oci_stmt_execute() already uses?

@@ -1020,6 +1020,20 @@ static int oci_stmt_col_meta(pdo_stmt_t *stmt, zend_long colno, zval *return_val
 	return SUCCESS;
 } /* }}} */
 
+static int oci_stmt_cursor_closer(pdo_stmt_t *stmt) /* {{{ */
+{
+	pdo_oci_stmt *S = (pdo_oci_stmt*)stmt->driver_data;
+
+	/* Without a closer, PDO drains the previous result with the fetcher, even on
+	 * DML / DDL handles (ORA-01002, ORA-03137 on PHP 8.4.27 / 8.5.12: GH-24372).
+	 * Only a query has a cursor: cancel it, as oci_stmt_execute() does. */
+	if (S && S->stmt && S->stmt_type == OCI_STMT_SELECT) {
+		OCIStmtFetch(S->stmt, S->err, 0, OCI_FETCH_NEXT, OCI_DEFAULT);
+	}
+
+	return 1;
+} /* }}} */
+
 const struct pdo_stmt_methods oci_stmt_methods = {
 	oci_stmt_dtor,
 	oci_stmt_execute,
@@ -1031,5 +1045,5 @@ const struct pdo_stmt_methods oci_stmt_methods = {
 	NULL, /* get_attr */
 	oci_stmt_col_meta,
 	NULL,
-	NULL
+	oci_stmt_cursor_closer
 };

With the core fix (d5696b8) the closer is also what PDO calls on re-execute, and closeCursor() now cancels the cursor in one call instead of fetching the remaining rows.

Tested on PHP 8.4.27 with this branch + the closer: SELECT re-executed with binds, partially fetched SELECT re-executed, SELECT with a BLOB column, closeCursor() + execute() (also with two closeCursor() calls), ALTER SESSION executed 3 times, PL/SQL block with IN/OUT binds. Without the closer, the ALTER SESSION case fails with ORA-01002.

I could not run DML on a real table here, so I added a test for CI. On 8.4.27 its ALTER SESSION part fails without the closer; on releases without the regression it passes either way:

tests/pdo_oci_reexecute_dml.phpt

--TEST--
PDO_OCI: Re-executing DML and DDL statements
--EXTENSIONS--
pdo
pdo_oci
--SKIPIF--
<?php
require(getenv('PDO_TEST_DIR').'/pdo_test.inc');
PDOTest::skip();
?>
--FILE--
<?php

require_once(getenv('PDO_TEST_DIR').'/pdo_test.inc');

$dbh = PDOTest::factory();
$dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

$dbh->exec("begin
             execute immediate 'drop table test_reexecute_dml';
             exception when others then
               if sqlcode <> -942 then
                 raise;
               end if;
           end;");
$dbh->exec('CREATE TABLE test_reexecute_dml (id NUMBER NOT NULL PRIMARY KEY, name VARCHAR2(20))');

$insert = $dbh->prepare('INSERT INTO test_reexecute_dml (id, name) VALUES (:id, :name)');
foreach ([1 => 'a', 2 => 'b', 3 => 'c'] as $id => $name) {
    $insert->execute([':id' => $id, ':name' => $name]);
}

$update = $dbh->prepare('UPDATE test_reexecute_dml SET name = :name WHERE id = :id');
$update->execute([':id' => 1, ':name' => 'a1']);
$update->execute([':id' => 2, ':name' => 'b1']);
$update->execute([':id' => 2, ':name' => 'b2']);
var_dump($update->rowCount());

$alter = $dbh->prepare("ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD'");
$alter->execute();
$alter->execute();
$alter->execute();
echo "alter session: ok\n";

$select = $dbh->prepare('SELECT name FROM test_reexecute_dml WHERE id = :id');
foreach ([1, 2, 3] as $id) {
    $select->execute([':id' => $id]);
    echo $select->fetchColumn(), "\n";
}

?>
--CLEAN--
<?php
require_once(getenv('PDO_TEST_DIR').'/pdo_test.inc');
$dbh = PDOTest::factory();
$dbh->exec('DROP TABLE test_reexecute_dml');
?>
--EXPECT--
int(1)
alter session: ok
a1
b2
c

The commit (closer + test + package.xml entry) is on top of this branch here: https://github.com/m3ct0n/pecl-database-pdo_oci/tree/pdo-oci-cursor-closer. I can open it as a PR against your branch if that's easier.

[iliaal]

Added the query-only closer and regression coverage for DML, ALTER SESSION, PL/SQL, and partially fetched queries. Verified on PHP 8.4.26 and 8.4.27, including explicit closeCursor(), repeated closure, and scrollable cursors. Thanks for the reproducer and proposed fix.

[sharadraju]

LGTM

[terabytesoftw]

Thks 👍