Citation:
One consequence of the SCN gap is that two consecutive SELECT statements can retrieve different data even though no DML has been executed between the two statements. For example, you can issue an update statement and then commit the update on the remote database. When you issue a SELECT statement on a view based on this remote table, the view does not show the update to the row. The next time that you issue the SELECT statement, the update is present.
You can use the following techniques to ensure that the SCNs of the two machines are synchronized just before a query:
*Because SCNs are synchronized at the end of a remote query, precede each remote query with a dummy remote query to the same site, for example, SELECT * FROM DUAL@REMOTE.
*Because SCNs are synchronized at the start of every remote transaction, commit or roll back the current transaction before issuing the remote query.
T'as pas eu la curiosité de faire une trace pour y voir plus clair ?