Copy method via dblink in MTK generates WAL logging

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Level 3 Adventurer

Copy method via dblink in MTK generates WAL logging

Hi Team,

 

I am using migation toolkit to migrate data from Oracle to EPAS using -fastcopy and -copyviadblinkora.

As per documentation, copyviadblinkora will use COPY API method and fastcopy will prevent wal logging to optimize migration.

When I am doing migration, there is a lot of WAL being generated.It took around 7 minutes for migration and during those 7 minutes 1200+ WALs were generated.

 

If WAL logging is disabled in fastcopy then why are so many WAL's generated?

 

Command used: 

/usr/edb/migrationtoolkit/bin/runMTK.sh -copyViaDBLinkOra -fastcopy -cpBatchSize 1024 -dataOnly -truncLoad -loaderCount 6 -allTables HR

 

 

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1 REPLY 1
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EDB Team Member

Re: Copy method via dblink in MTK generates WAL logging

Hi Nikhil,
 
fastcopy uses Copy API which bypasses WAL logging​ where​ copyViaDBlink actually connects directly to source Oracle​.​
So combination both will not bypass WAL logging.
 
Regards,
Prasad

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