You were brought to this page based on an internet search
and as a free service to Oracle DBAs.
The text below is an except from the book,
Oracle Performance Firefighting, written by
Craig Shallahamer of
OraPub, Inc.
Figures and tables are not included on this page, only their reference.
To order the book in either print or PDF form, click
here.
©2009, 2010 by Craig Shallahamer. This is copyrighted material.
PleaseOut of respect for those involved in the creation of the book and also for
their familes, we ask you to respect the copyright both in intent and deed. Thank you.
-------------------------------
* Xid: This is the transaction ID, which is a concatenation of the transaction table ID (in Figure 6-37, 0003), the transaction's transaction table's slot number (in Figure 6-37, 00d), and the sequence number (in Figure 6-37, 0000318). The transaction ID is important, as it is used to ensure seemingly related undo information is truly related.
* Uba: This is the undo block address. This points directly to the transaction's most recent change undo and is necessary for rolling back a transaction and also for read consistency (cloned buffer construction) purposes.
* Flag: The flag is a status of the transaction and can take on many values. The following are the most common:
©2009, 2010 by Craig Shallahamer. This is copyrighted material.
PleaseOut of respect for those involved in the creation of the book and also for
their familes, we ask you to respect the copyright both in intent and deed. Thank you.
|