fixes #2637: fix closing prepared statement cursor with LOB column on Oracle

lib/Doctrine/DBAL/Driver/OCI8/OCI8Statement.php

@@ -188,11 +188,7 @@ class OCI8Statement implements \IteratorAggregate, Statement
             return true;
         }
 
-        // emulate it by fetching and discarding rows, similarly to what PDO does in this case
-        // @link http://php.net/manual/en/pdostatement.closecursor.php
-        // @link https://github.com/php/php-src/blob/php-7.0.11/ext/pdo/pdo_stmt.c#L2075
-        // deliberately do not consider multiple result sets, since doctrine/dbal doesn't support them
-        while (oci_fetch($this->_sth));
+        oci_cancel($this->_sth);
 
         $this->result = false;
 

tests/Doctrine/Tests/DBAL/Functional/StatementTest.php

@@ -15,6 +15,7 @@ class StatementTest extends \Doctrine\Tests\DbalFunctionalTestCase
 
         $table = new Table('stmt_test');
         $table->addColumn('id', 'integer');
+        $table->addColumn('name', 'text', array('notnull' => false));
         $this->_conn->getSchemaManager()->dropAndCreateTable($table);
     }
 
@@ -225,6 +226,19 @@ EOF
         $this->assertTrue($stmt->closeCursor());
     }
 
+    /**
+     * @group DBAL-2637
+     */
+    public function testCloseCursorAfterCursorEnd()
+    {
+        $stmt = $this->_conn->prepare('SELECT name FROM stmt_test');
+
+        $stmt->execute();
+        $stmt->fetch();
+
+        $this->assertTrue($stmt->closeCursor());
+    }
+
     /**
      * @dataProvider emptyFetchProvider
      */