Fetching of data from database while updating data X dating sites
For example, a function could access a table whose data is changed and committed by another user.
For each execution of the When a transaction runs in serializable mode, all data accesses reflect the state of the database as of the time the transaction began.
However, they do not see the changes made by the DML statement itself.
The rollback segments contain the old values of data that have been changed by uncommitted or recently committed transactions.