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Restructure pg_opclass, pg_amop, and pg_amproc per previous discussions in

pgsql-hackers.  pg_opclass now has a row for each opclass supported by each
index AM, not a row for each opclass name.  This allows pg_opclass to show
directly whether an AM supports an opclass, and furthermore makes it possible
to store additional information about an opclass that might be AM-dependent.
pg_opclass and pg_amop now store "lossy" and "haskeytype" information that we
previously expected the user to remember to provide in CREATE INDEX commands.
Lossiness is no longer an index-level property, but is associated with the
use of a particular operator in a particular index opclass.

Along the way, IndexSupportInitialize now uses the syscaches to retrieve
pg_amop and pg_amproc entries.  I find this reduces backend launch time by
about ten percent, at the cost of a couple more special cases in catcache.c's
IndexScanOK.

Initial work by Oleg Bartunov and Teodor Sigaev, further hacking by Tom Lane.

initdb forced.
This commit is contained in:
Tom Lane
2001-08-21 16:36:06 +00:00
parent c2d1566912
commit f933766ba7
60 changed files with 1918 additions and 1929 deletions

View File

@ -1,10 +1,10 @@
This is an implementation of RD-tree data structure using GiST interface
of PostgreSQL. It has built-in lossy compression - must be declared
in index creation - with (islossy). Current implementation provides index
support for one-dimensional array of int4's - gist__int_ops, suitable for
small and medium size of arrays (used on default), and gist__intbig_ops for
indexing large arrays (we use superimposed signature with length of 4096
bits to represent sets).
of PostgreSQL. It has built-in lossy compression.
Current implementation provides index support for one-dimensional array of
int4's - gist__int_ops, suitable for small and medium size of arrays (used on
default), and gist__intbig_ops for indexing large arrays (we use superimposed
signature with length of 4096 bits to represent sets).
All work was done by Teodor Sigaev (teodor@stack.net) and Oleg Bartunov
(oleg@sai.msu.su). See http://www.sai.msu.su/~megera/postgres/gist
@ -35,7 +35,7 @@ EXAMPLE USAGE:
-- create indices
CREATE unique index message_key on message ( mid );
CREATE unique index message_section_map_key2 on message_section_map (sid, mid );
CREATE INDEX message_rdtree_idx on message using gist ( sections gist__int_ops) with ( islossy );
CREATE INDEX message_rdtree_idx on message using gist ( sections gist__int_ops);
-- select some messages with section in 1 OR 2 - OVERLAP operator
select message.mid from message where message.sections && '{1,2}';