ORACLE : Quiescing database
Schema changes, reorganizations or other administrative tasks are difficult to make while users area conducting live transactions in the database. You have to perform these activity during a schedulated maintenance or you have to shut down the database and reopen in “restricted mode”. For obviate this problem , “quescing database” gives the possibility to put the database in single mode without having to ever shutdown the database. When a database is in “quiesced state” the following conditions apply: All inactive sessions are prevented from issuing any database commands until the database in in “unquiesced state”. All active sessions are...