I want to know what's the correct command that I can use inside a SQL Statement that provides me to read uncommited transactions belonging to other users?
For instance, I submit this select:
Select * from employees;
What can I do in the sql statement above to read also all the records in the employees table that were not commited by other users...
I hope somebody will answer me,
Oracle does not allow dirty reads, and hence does not even support the read uncommitted isolation level
To Oracle, dirty reads are EVIL (and I do agree). You might want to have a look at the following site http://asktom.oracle.com and search for "dirty read"
<<<FROM THE ORACLE DOCUMENTATION>>>
This is the default transaction isolation level. Each query executed by a transaction sees only data that was committed before the query (not the transaction) began. An Oracle query never reads dirty (uncommitted) data.
I agree and would like to add that serialization determines the point in time from which you can see committed data. Either you can see new commits during your query, or you only data that was committed prior to your query. There is no way to see uncommitted data.
When a user updates a row, an flag is set on that row which tells all other users to use data stored in the rollback/undo segment. You cannot unset that flag, and so you have no way to see the uncommitted data.