In response to Waldomiro :
> I?m thinking It hapens because in the 7 millions tables, the same 8k
> block has diferent records with different keys, so only a few records
> with 'my_key' is retrieved when I read a 8k block.
> In the part_table, all records stored in a 8k block have 'my_key', so
> It?s much optimized.
>
> My doubt, there is a way to defrag my 7 millions table to put all
> records with the same key in the same 8k block?
>
> How can I do that?
CLUSTER your table:
http://www.postgresql.org/docs/current/static/sql-cluster.html
Andreas
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Andreas Kretschmer
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