[thelist] Table Update Schedule Answer

rudy r937 at interlog.com
Thu Apr 19 13:56:02 CDT 2001


ron, thanks for the kind words, but i'm afraid that's not what i meant

=o)

my idea was to copy your updated database over top of your reporting
database

i'm trying to keep in mind what you said originally --

> I don't want users to see the report with "half updated"
> records.  I want them to get the complete noon report
> or the complete midnight report.  Currently I'm taking
> the report "down" twice a day for about an hour

don't take the reporting database down, do the update to an offline master
copy

while you are updating the master, let the users continue to run queries
off the reporting database

when you are done updating the offline master version of the database, just
copy it over top of the reporting database

this is usually a very fast process, you may not even have to take the
reporting database down to do it

okay, the master copy of the database that you update offline, while people
keep querying the reporting database, is your system of record database and
you apply all the standard safeguards to it, like logging, backup and
recovery, and so on

the reporting database is simply refreshed whenever you are done updating
the master, by copying the master over top of it

also, that way if the update takes three hours instead of one, nobody
notices an outage, just that the data only becomes "fresher" around 3 pm

helps?

rudy





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