>
>
> Hmm, let me guess ...
>
> one of the overhead elements for each row header is pointer to the next
> row, right ? That way the summing-up of varlena types is avoided, although
> the postgres engine still has to go from row header to row header to find
> Nth row in a page (block), right
>hmm, thus if one block has 8192 bytes, and if there is 9-byte overhead
> for each row, then I can store 390 rows in one block if, on average,
> "names" are 10 chars in length ? echo $[ 8192 / ( 9 + 10 + 2 ) ] # = 390
Yes. See FAQ for row overhead calculations.
>If each record has varia
Hmm, let me guess ...
one of the overhead elements for each row header is pointer to the next
row, right ? That way the summing-up of varlena types is avoided, although
the postgres engine still has to go from row header to row header to find
Nth row in a page (block), right ?
Thx,
