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For how many years have you been working with physical servers that are starving your database of the memory necessary to deploy important new performance features such as the Result Cache, Memoptimize Pool, In-Memory Aggregation, In-Memory Column Store, and Full Database Caching? Too long? Contact me to learn how to improve all queries ... not just some queries.
Purpose Assumes that a primary database and one or more Data Guard physical standby databases are deployed. The databases should be at least mounted or open before block comparison is run.

Logical standby databases, Far Sync instances, and cascaded standbys cannot be the target database.
Documented Yes
First Available
Security Model Owned by SYS with EXECUTE granted to SYSBACKUP and SYSDG.
Source {ORACLE_HOME}/rdbms/admin/dbmsdbcomp.sql
Compares database blocks on primary to standby(s) dbms_dbcomp.dbcomp(
datafile   IN VARCHAR2,
outputfile IN VARCHAR2,
block_dump IN BOOLEAN := FALSE);
exec dbms_dbcomp.dbcomp('ALL', '/home/oracle/lost_write_check.txt', TRUE);

-- in a separate SQL*Plus session
SELECT target_desc, sofar, totalwork
FROM v$session_longops
WHERE opname = 'BlockCompare';

TARGET_DESC                      SO FAR  TOTALWORK
----------------------------- --------- ----------
Compared Blocks                  367104     403142
Lost Writes                           0          0

Related Topics
Built-in Functions
Built-in Packages
Data Guard
Dumping Oracle
What's New In 12cR2
What's New In 18cR3

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