How to find out when an Oracle table was updated the last time

Question

Can I find out when the last INSERT, UPDATE or DELETE statement was performed on a table in an Oracle database and if so, how?

A little background: The Oracle versio

Answer 1

I'm really late to this party but here's how I did it:

SELECT SCN_TO_TIMESTAMP(MAX(ora_rowscn)) from myTable;

It's close enough for my purposes.

Answer 2

SELECT * FROM all_tab_modifications;

Answer 3

Oracle can watch tables for changes and when a change occurs can execute a callback function in PL/SQL or OCI. The callback gets an object that's a collection of tables which changed, and that has a collection of rowid which changed, and the type of action, Ins, upd, del.

So you don't even go to the table, you sit and wait to be called. You'll only go if there are changes to write.

It's called Database Change Notification. It's much simpler than CDC as Justin mentioned, but both require some fancy admin stuff. The good part is that neither of these require changes to the APPLICATION.

The caveat is that CDC is fine for high volume tables, DCN is not.

Answer 4

How long does the batch process take to write the file? It may be easiest to let it go ahead and then compare the file against a copy of the file from the previous run to see if they are identical.

Answer 5

If any one is still looking for an answer they can use Oracle Database Change Notification feature coming with Oracle 10g. It requires CHANGE NOTIFICATION system privilege. You can register listeners when to trigger a notification back to the application.