[GENERAL][HACKERS]data fragmentation

Hi,

i have a theorical question. i was thought that data fragmentation can cause
a
loss of performance when retrieving data from a database. Some DBMS solved
this
with dbspaces, but postgresql doesn't support this concept.
so, pgsql databases tend to suffer from data fragmentation?
if yes, what is the solution you recommend?

also i was thought that even when DBMS support dbspaces DELETEing records
may
cause data fragmentation anyway.
so, can i think of DELETE statement as a double-edged sword?
it is indifferent in pgsql - it doesn't support dbspaces anyway?

thanks in advance,
Jaime Casanova (el_vigia)

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