Thanks for the question, Rajneesh.
Asked: April 28, 2020 - 8:07 am UTC
Last updated: May 01, 2020 - 7:42 am UTC
Version: oracle 19c
Viewed 1000+ times
You Asked
Hi TOM,
I have heard that too often gather stats on DB schema may have adverse effect on performance than improving query response time? Is it correct ? If yes then why so?
Also please list out what all main examples of data base maintenance activities related to ETL batch load from OLTP to OLAP (in target database) and examples why they require. This is to gain insight on Data warehouse DB requirements from maintenance perspective.
Thanks,
Rajneesh
and Connor said...
Gathering statistics (using the default parameters) only gather those stats that are needed, so if the stats are up to date then gathering will do minimal work. But if you sway away from the default parameters, then all bets are off.
Having said that, no-one ever says to a DBA ... "Hey, what great stats you have". Good statistics are never a *goal*, they are a means to have good performing queries to meet business requirements.
The main activities of ETL are right there in the name.... extract, transform, load. And you don't even need to obey those strictly. It can be:
"STL" - stream transform load
"TEL" - transform extract load
"SLT" - stream load transform
etc etc.... Don't get bogged down by process, focus on what works best for the business requirement at hand.
Rating
(1 rating)
Is this answer out of date? If it is, please let us know via a Comment