Re: Long Running Update - Mailing list pgsql-performance

From Harry Mantheakis
Subject Re: Long Running Update
Date
Msg-id 4E04BB75.4070403@riskcontrollimited.com
Whole thread Raw
In response to Re: Long Running Update  ("Kevin Grittner" <Kevin.Grittner@wicourts.gov>)
Responses Re: Long Running Update  ("Kevin Grittner" <Kevin.Grittner@wicourts.gov>)
List pgsql-performance
Thank you so much for all the feedback, Kevin - much appreciated.

I have stopped the all-in-one-go update from executing, and now I am
executing a series of statements, each constrained to update no more
than 100,000 records at a time.

Interesting fact: updating 100,000 rows takes 5 seconds. Quick.

I tried updating 1 million rows in one go, and the statement was still
running after 25 minutes, before I killed it!

So I am now executing an SQL script with almost 800 separate
update-statements, each set to update 100K records, and the thing is
trundling along nicely. (I am fortunate enough to be surrounded by
MatLab users, one of whom generated the 800-statement file in one minute
flat!)

Many thanks again for all the info.

Kind regards

Harry Mantheakis
London, UK


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