Initialization Parameter

UNDO_RETENTION, How and Why

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UNDO_RETENTION At times, you may find out or feel that UNDO_RETENTION is useless at all. Raising the number of seconds cannot resolve ORA-01555. This is true under some specific conditions. Here I quote the requisites from the official document below: Fix-sized Undo Tablespace The UNDO_RETENTION parameter is ignored for a fixed size undo tablespace. The […]
Initialization Parameter

Timings to Set SESSIONS Explicitly

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DBAs usually set PROCESSES when initializing a new database:SQL> alter system set processes=3000 scope=both;System altered.Another important parameter SESSIONS will be derived from PROCESSES automatically in this manner:SESSIONS = (1.5 * PROCESSES) + 22In a dedicated server environment, the derived value of SESSIONS could be somewhat close to the facts of database. You can accept the value […]
Initialization Parameter

How to Resolve ORA-02097: Parameter Cannot be Modified Because Specified Value is Invalid

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When you ALTER SYSTEM to modify an initialization parameter, it sometimes fails with ORA-02097 ORA-02097: parameter cannot be modified because specified value is invalid Reproduce ORA-02097 Let’s me show you some examples that can reproduce ORA-02097 and I will explain it more detailed along with the context. Here I would like to change DB_RECOVERY_FILE_DEST location. […]
Archived Log File

How to Archive Redo Logs to Respective Local Destinations of RAC

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For a RAC database, we may want to archive the redo logs to local destinations of instances rather than ASM. That is, put instance #1, #2 archive thread #1, #2 redo logs to their respective local destinations. To achieve this goal, LOG_ARCHIVE_DEST_1 should be setup more granularly by sid like this way:SQL> alter system set log_archive_dest_1=’location=/oracle/oradata/arch1′ […]