From: | Zeugswetter Andreas SB <ZeugswetterA(at)wien(dot)spardat(dot)at> |
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To: | "'Tom Lane'" <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
Cc: | pgsql-hackers(at)postgresql(dot)org |
Subject: | AW: pg_attribute growing and growing and growing |
Date: | 2000-08-21 09:28:03 |
Message-ID: | 11C1E6749A55D411A9670001FA687963368058@sdexcsrv1.f000.d0188.sd.spardat.at |
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Lists: | pgsql-hackers |
> foo=# \d pg_attribute_relid_attnam_index
> Index "pg_attribute_relid_attnam_index"
> Attribute | Type
> -----------+------
> attrelid | oid
> attname | name
> unique btree
>
> foo=# \d pg_attribute_relid_attnum_index
> Index "pg_attribute_relid_attnum_index"
> Attribute | Type
> -----------+----------
> attrelid | oid
> attnum | smallint
> unique btree
>
> Since table OIDs keep increasing, this formulation ensures that new
> entries will always sort to the end of the index, and so space freed
> internally in the indexes can never get re-used. Swapping the column
> order may eliminate that problem --- but I'm not sure what if any
> speed penalty would be incurred. Thoughts anyone?
Isn't pg_attribute often accessed with a "where oid=xxx" restriction
to get all cols for a given table ?
Andreas
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