table lock ? dictionary row lock? recursive?
620942Jul 10 2009 — edited Jul 13 2009hi guys,
was looking at dml locks and ddl locks
for example
--------------------
DML changes to table tab
1) (TX lock for table tab's affected row - stored in the row itself)
2) (TM lock for table tab - store in V$lock)
DDL changes to table tab
1) (DDL lock for table tab -> store in v$lock ?)
2) (TX lock for dictionary affected row -> locking that row in data dictionary tab to reflect changes)
3) (TM lock for dictionary tab -> store in V$lock ?)
(Since i doing a DML to the data dictionary table, am i going to hold another TM lock for that data dictionary table)
what is a DDL lock exactly?
1) a lock on the table tab in v$lock
or
2) or tx lock on the data dictionary row (which will then incurr a recursive TM lock the data dictionary table)
or ?
please advise!