Detect chained and migrated rows in Oracle – Part 1 | Tanel Poder Consulting

[utterances-bot]

Detect chained and migrated rows in Oracle – Part 1 | Tanel Poder Consulting

I received a question about migrated rows recently.
It was about how to detect migrated rows in a 200TB data warehouse, with huge tables – as the ANALYZE TABLE xyz LIST CHAINED ROWS INTO command can not be automatically parallelized at table level (as DBMS_STATS can be, but oh, DBMS_STATS doesn’t gather the migrated/chained row info). Therefore the analyze command would pretty much run forever before returning (and committing) the chained row info in the output table. Also as there are regular maintenance jobs running on these tables (I suspect partition maintentance for example), then it wouldn’t be nice to keep running ANALYZE on the whole table constantly.
So, is there any faster or better way for fin

https://tanelpoder.com/2009/11/04/detect-chained-and-migrated-rows-in-oracle/

[cityvigil]

nice~