Menggunakan Oracle dan PHP:Bekerja di SQL Developer tetapi hasil file PHP ORA-00900:Pernyataan Tidak Valid

Saya pikir saya sudah mengetahuinya. Tampaknya perlu membuat prosedur dari skrip PL/SQL itu:

CREATE OR REPLACE PROCEDURE getExamStatus(RC OUT SYS_REFCURSOR) AS
    exam_ids   VARCHAR2(255);
BEGIN
    SELECT
        LISTAGG(''''
                  || exam_id
                  || ''' AS \"'
                  || exam_name
                  || '\"',',') WITHIN GROUP(
            ORDER BY
                exam_id ASC
        )
    INTO exam_ids
    FROM
        exam;

    OPEN rc FOR 'SELECT
        *
               FROM
        (
            SELECT
                u.user_id,
                u.user_name,
                e.exam_id,
                eu.exam_date
            FROM
                users u
                LEFT JOIN exam_user eu ON u.user_id = eu.user_id
                LEFT JOIN exam e ON e.exam_id = eu.exam_id
            ORDER BY
                u.user_id
        )
            PIVOT ( MAX ( exam_date )
                FOR exam_id
                IN ( ' || EXAM_IDS || ' )
            )
    ORDER BY
        1';
END;
/

Kemudian jalankan prosedur itu di database. Setelah itu di file PHP saya harus refactor pernyataan sql:

$sql = "BEGIN getExamStatus(:rc); END;";

Dan fungsinya:

function getSQLResult($sql, $conn) {
    $stmt = oci_parse($conn, $sql);

    if( $stmt === false ) {
        errorShutdown(__('...'), __('...'));
        die();
    } else {
        $rc = oci_new_cursor($conn);
        oci_bind_by_name($stmt, ':rc', $rc, -1, OCI_B_CURSOR);
        if(!oci_execute($stmt)) {
            return false;
            //return oci_error($stmt);
        }
        if(!oci_execute($rc)) {
            return false;
            //return oci_error($stmt);
        }
        $results = array();
        while (($row = oci_fetch_array($rc, OCI_ASSOC+OCI_RETURN_NULLS)) != false) {
            $results[] = $row;
        }
        oci_free_statement($stmt);
        oci_free_statement($rc);
        return $results;
    }
}