** it seemed safer to do this whole operation in "write" mode.
**
** We tell the data dictionary we're done writing at the end of
** the transaction.
*/
dd.startWriting(lcc);
// need to lock heap in exclusive mode first. Because we can't first
// shared lock the row in SYSCONGLOMERATES and later exclusively lock
// it, this is potential deadlock (track 879). Also td need to be
// gotten after we get the lock, a concurrent thread could be modifying