Re: Re: Postgresql bulk fast loader

Mark Volpe wrote:
>
> Avoid doing this with indexes on the table, though. I learned the hard way!
>
> Mark
>
> mlw wrote:
> >
> > Naomi Walker wrote:
> > >
> > > Does postgresql have any sort of fast bulk loader?
> >
> > It has a very cool SQL extension called COPY. Super fast.
> >
> > Command: COPY
> > Description: Copies data between files and tables
> > Syntax:
> > COPY [ BINARY ] table [ WITH OIDS ]
> > FROM { 'filename' | stdin }
> > [ [USING] DELIMITERS 'delimiter' ]
> > [ WITH NULL AS 'null string' ]
> > COPY [ BINARY ] table [ WITH OIDS ]
> > TO { 'filename' | stdout }
> > [ [USING] DELIMITERS 'delimiter' ]
> > [ WITH NULL AS 'null string' ]
> >
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Hi

On a daily basis I have an automated procedure that that bulk copies
information into a "holding" table. I scan for duplicates and put the
OID for the first unique record into a temporary table. Using the OID
and other information I do an INSERT with SELECT to move the unique
data into its appropriate table. Then I remove the unique records and
move the duplicates into a debugging table. After that I remove the
remaining records and drop the temporary tables. Once this is done I
vacuum the tables and regenerate the indexes.

This sounds complicated but by doing things in quick simple transactions
the database is able to run continuously without disruption. I am able
to import 30+ MB of data every day with only a small disruption when
updating the the summary tables.

Guy Fraser

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