Pierre C schrieb:
>
>> Within the data to import most rows have 20 till 50 duplicates.
>> Sometime much more, sometimes less.
>
> In that case (source data has lots of redundancy), after importing the
> data chunks in parallel, you can run a first pass of de-duplication on
> the chunks, also in parallel, something like :
>
> CREATE TEMP TABLE foo_1_dedup AS SELECT DISTINCT * FROM foo_1;
>
> or you could compute some aggregates, counts, etc. Same as before, no
> WAL needed, and you can use all your cores in parallel.
>
> From what you say this should reduce the size of your imported data by
> a lot (and hence the time spent in the non-parallel operation).
Thank you very much for this advice. I've tried it inanother project
with similar import-problems. This really speed the import up.
Thank everyone for your time and help!
Greetings,
Torsten
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