Ulfat`s DataBase Blog

Oracle 11g has several new features. Today I will stay on DataPump technologies which was extended and enhanced EXP/IMP which first time was introduced on Oracle 10g. Here are main features: Compression Encryption Transportable Partition Option Data Options Reuse Dumpfile(s) Remap_table Remap Data http://www.oracle.com/technetwork/database/datapump11g2009-featureover-134227.pdf   One of the main and essential feature is Partition option. Because if table size more than a little bit Gbytes and if table is partitioned how to transport this partition tables using EXPDP ?     You can now export one or more partitions of a table without having to move the entire table.  On import, you can choose to load partitions as is, merge them into a single table, or promote each into a separate table.  Example: SQL> conn /as sysdba Connected. SQL> create user ulfet identified by ulfet; User creat...

I know you know what will happen if you lost one or all your online redo files. Always multiplex your Redo logs (controlfile too) and store it several partitions. So, one of student did not it and requested to me what to do. For him I prepare this tutorial.:) If your Redo log files are multiplexed and you lost one of the member of redo file do not panic, just copy another member of same group and paste it with lost member place. Suppose you have 3 groups (redo1, redo2, redo3) and all group has three members (redo1a, redo1b, redo1c, ...) If you lost redo1a.log just take  redo1b.log and copy it where should be  redo1a.log and do not forget to rename it to redo1a.log. /u01/oradata/mydb/ redo1a.log redo2a.log redo3a.log /u02/oradata/mydb/ redo1b.log redo2b.log redo3b.log /u03/oradata/mydb/       redo1c.log redo2c.log redo3c.log If your redo logs were not multiplexed and you lost redo files then follow me: [oracle@localhost ~]$ hostname localhost....

Oracle Streams is one of the solution to replication. Oracle has several solutions : Replication, Golden Gate, Streams. Streams has a lot of advantages, one and main is data can be replicate between Oracle to non Oracle services. Brief info about streams. Oracle Streams captures database changes at a source database, stages the changes, propagates the changes to one or more destination databases, and then applies the changes at the destination database(s). Using Oracle Streams, enterprise systems can capture, propagate, and apply information as follows: Within an Oracle database Between two Oracle databases Among multiple Oracle databases Between an Oracle database and a non-Oracle database How Streams Works Oracle Streams begins by capturing changes. The changes (to data, tables, schemas, and so on) that take place in a database are recorded in the database redo log files. The Streams capture process extracts these changes from the redo log files and formats each change ...