Ühel kenal päeval, E, 2007-10-08 kell 12:12, kirjutas Gokulakannan
Somasundaram:
> Hi,
> Currently The index implementation in Postgresql does not store
> the Snapshot information in the Index.
..
> Please reply back with your comments.
I think you got enoght "search for previous discussion" answers on this
aone already ;)
So I propose a few another ideas to investigate
1. get rid of indexes for TOAST tables
instead of TOAST tuple id store CTID of first TOAST block directly, and
use something like skip lists inside the TOAST block headers to access
next TOAST tuples.
2. store visibility info in TOAST tables
if you store visibility info in TOAST tuples, it becomes possible to
update just the small part of the tuple in the main heap and keep the
bulk of toasted data in place.
both of these ideas are much more complicated to implement than it
appears from my simple description, but should have big benefits for a
sizable number of scenarios which use TOAST.
-------------
Hannu
---------------------------(end of broadcast)---------------------------
TIP 9: In versions below 8.0, the planner will ignore your desire to
choose an index scan if your joining column's datatypes do not
match
