Tom Lane wrote:
> of dead tuples followed by a lot of pages worth of live tuples. Plain
> VACUUM cannot do much to fix this since it doesn't move rows around.
> VACUUM FULL will fix it, but its index-update overhead is high enough
> that CLUSTER is a better deal.
Tom: I was interested in performance improvements from cluster, so I
tried to cluster a table on a spatial index:
dra_working=# \d geomtest Table "public.geomtest" Column | Type | Modifiers
----------------+----------+----------- rd_segment_id | integer | admit_date | date | retire_date | date
| most_recent | boolean | lineargeometry | geometry |
Indexes: geomtest_idx gist (lineargeometry)
dra_working=# cluster geomtest_idx on geomtest;
ERROR: CLUSTER: cannot cluster when index access method does not handle
nulls
You may be able to work around this by marking column "lineargeometry"
NOT NULL
dra_working=# select version(); version
--------------------------------------- PostgreSQL 7.3.6 on i686-pc-linux-gnu
As of quite a while ago (7.2?) the GiST access method was made null-safe
by Teodor and Oleg, I think. Is this a safety wrapper left over from
before the upgrade to GiST?
-- __ / | Paul Ramsey | Refractions Research | Email: pramsey@refractions.net | Phone: (250)
885-0632 \_
