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Excluding LOB Columns Data in Data Pump

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  We intend to create a dump from a table in which some columns contain LOB data. However, due to the large volume of LOB data in this table — and for reasons such as higher speed, better security, or reduced space allocation — we want to prevent this data from being included in the dump file, or at least prevent it from being restored during the import process. What is the solution? Excluding LOB column data during the  export  operation in Oracle 12c can be easily controlled. This can be done by creating a view and using the  VIEWS_AS_TABLES  parameter. However, if the dump file already contains LOB data, this method cannot be used during import. In such cases, the  REMAP_DATA  parameter is the solution. Previously, we explained that the  REMAP_DATA  parameter can be used for data masking and data manipulation during export and import operations. In this article, we will see how the same parameter can be used to exclude LOB column data duri...
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Restoring a Datafile Using Archivelogs

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  Suppose a datafile that was recently added to the database is lost for some reasons. In this case, if the archive logs from the time the datafile was created are available, it is possible to recover that datafile. However, as mentioned, this operation has a very strict requirement: “All archive logs from the time the datafile was created must be available.” Below, we will walk through a scenario related to this topic. SQL > archive log list; Database log mode Archive Mode SQL > alter table space USEF_TBS add datafile ‘ / acfs / test2.dbf’ size 10 m; With the following commands, we create a new table that uses space from the new datafile so that after recovery we can verify that no data was lost. SQL > create table usef_tbl1 tablespace usef_tbs as select * from dba_tables where 1 = 2 ; SQL > alter table usef_tbl1 ALLOCATE EXTENT(DATAFILE ‘ / acfs / test2.dbf’ size 5 m); Table altered. SQL > insert into usef_tbl1 select * from ...
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Oracle AI Database 26ai — Managing AWR in Active Data Guard

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  Starting with   Oracle Database 12.2 , generating   AWR reports on an  Active Data Guard (ADG) standby  became possible by using the  Remote Management Framework (RMF) . In this model, AWR data had to be manually transported from the standby to the primary database. Although functional, the setup was complex and required multiple configuration steps, making AWR analysis on physical standby databases operationally challenging for DBAs. With  Oracle Database 26ai , AWR support for  Active Data Guard Standby  databases is fully integrated and enabled by default. AWR snapshots are automatically collected on the ADG standby and transparently transported to the  primary database , without any manual intervention or RMF configuration. By default, snapshots are taken  once per hour , and the  retention period is 8 days . This enhancement allows DBAs to work with AWR on an Active Data Guard standby in the same way as on the primary da...
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