The following script runs fine the first time:

<?
        $id = dba_open ("testdb.db", "c", "db3");

        if (!$id) {
                echo "dba_open failed\n";
                exit;
        }

        dba_close($id);
?>

But second time (after the DB is created) it fails. After a long day of research, I found the Berkley DB code changed:

db-3.2.9/db/db.c:

        switch (type) {
        case DB_UNKNOWN:
                if (LF_ISSET(DB_CREATE|DB_TRUNCATE)) {
                        __db_err(dbenv,
            "%s: DB_UNKNOWN type specified with DB_CREATE or DB_TRUNCATE",
                            name);
                        return (EINVAL);
                }
                ok_flags = 0;
                break;
        case DB_BTREE:
                ok_flags = DB_OK_BTREE;
                break;
        case DB_HASH:
                ok_flags = DB_OK_HASH;
                break;
        case DB_QUEUE:
                ok_flags = DB_OK_QUEUE;
                break;
        case DB_RECNO:
                ok_flags = DB_OK_RECNO;
                break;
        default:
                __db_err(dbenv, "unknown type: %lu", (u_long)type);
                return (EINVAL);
        }

When using "c" mode in dba_open, if the file does not exist, PHP calls dbp->open as:

dbp->open(dbp, <file>, NULL, 1, 1, 420)

When using "c" mode and the file does not exist, it calls dbp->open as:

dbp->open(dbp, <file>, NULL, 5, 1, 420)

DB_UNKNOWN and DB_CREATE are no longer valid options to pass together.

My fix was to change ext/dba/dba_db3.c as follows:

Before 
------
        type =  info->mode == DBA_READER ? DB_UNKNOWN :
                info->mode == DBA_TRUNC ? DB_BTREE :
                VCWD_STAT(info->path, &check_stat) ? DB_BTREE : DB_UNKNOWN;

After
-----
        type =  info->mode == DBA_READER ? DB_UNKNOWN :
                info->mode == DBA_TRUNC ? DB_BTREE :
                (VCWD_STAT(info->path, &check_stat) ||
                 (info->mode == DBA_CREAT) || (info->mode == DBA_TRUNC)) ? DB_BTREE : DB_UNKNOWN;

The only other way to solve this would be to attempt to determine the type of DB before trying to open it, as the PHP interface does not give the capability to distinguish between BTREE/RECNO/HASH/QUEUE/etc.

This should solve the following bug reports:

http://bugs.php.net/bug.php?id=10798
http://bugs.php.net/bug.php?id=13358
http://bugs.php.net/bug.php?id=8574
http://bugs.php.net/bug.php?id=11732
http://bugs.php.net/bug.php?id=10380

HTH,
Nathan Clemons,
Director of Virtual E-Services Network, Inc.