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.

1 files changed, 200 insertions, 138 deletions

diff --git a/contrib/rtree_gist/rtree_gist.sql.in b/contrib/rtree_gist/rtree_gist.sql.in
index 68fe8b5edb8..c030fe471bb 100644
--- a/contrib/rtree_gist/rtree_gist.sql.in
+++ b/contrib/rtree_gist/rtree_gist.sql.in
@@ -21,123 +21,154 @@ create function gbox_union(bytea, opaque) returns box as 'MODULE_PATHNAME' langu
 
 create function gbox_same(box, box, opaque) returns opaque as 'MODULE_PATHNAME' language 'C';
 
--- add a new opclass
---INSERT INTO pg_opclass (opcname, opcdeftype)
---   SELECT 'gist_box_ops', oid
---   FROM pg_type
---   WHERE typname = 'box';
-INSERT INTO pg_opclass (opcname, opcdeftype) values ( 'gist_box_ops', 0 );
-
---SELECT oid, opcname FROM pg_opclass WHERE opcname = 'gist_box_ops';
+-- add a new opclass (non-default)
+INSERT INTO pg_opclass (opcamid, opcname, opcintype, opcdefault, opckeytype)
+    VALUES (
+        (SELECT oid FROM pg_am WHERE amname = 'gist'),
+        'gist_box_ops',
+        (SELECT oid FROM pg_type WHERE typname = 'box'),
+        false,
+        0);
 
 -- get the comparators for boxes and store them in a tmp table
 SELECT o.oid AS opoid, o.oprname
-INTO TABLE rt_ops_tmp
+INTO TEMP TABLE rt_ops_tmp
 FROM pg_operator o, pg_type t
 WHERE o.oprleft = t.oid 
    and t.typname = 'box';
 
 -- using the tmp table, generate the amop entries 
 -- box_left
-INSERT INTO pg_amop (amopid, amopclaid, amopopr, amopstrategy) 
-   SELECT am.oid, opcl.oid, c.opoid, 1
-   FROM pg_am am, pg_opclass opcl, rt_ops_tmp c
-   WHERE amname = 'gist' and opcname = 'gist_box_ops' 
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr) 
+   SELECT opcl.oid, 1, false, c.opoid
+   FROM pg_opclass opcl, rt_ops_tmp c
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_box_ops' 
       and c.oprname = '<<';
 
 -- box_overleft
-INSERT INTO pg_amop (amopid, amopclaid, amopopr, amopstrategy) 
-   SELECT am.oid, opcl.oid, c.opoid, 2
-   FROM pg_am am, pg_opclass opcl, rt_ops_tmp c
-   WHERE amname = 'gist' and opcname = 'gist_box_ops' 
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr) 
+   SELECT opcl.oid, 2, false, c.opoid
+   FROM pg_opclass opcl, rt_ops_tmp c
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_box_ops' 
       and c.oprname = '&<';
 
 -- box_overlap
-INSERT INTO pg_amop (amopid, amopclaid, amopopr, amopstrategy) 
-   SELECT am.oid, opcl.oid, c.opoid, 3
-   FROM pg_am am, pg_opclass opcl, rt_ops_tmp c
-   WHERE amname = 'gist' and opcname = 'gist_box_ops' 
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr) 
+   SELECT opcl.oid, 3, false, c.opoid
+   FROM pg_opclass opcl, rt_ops_tmp c
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_box_ops' 
       and c.oprname = '&&';
 
 -- box_overright
-INSERT INTO pg_amop (amopid, amopclaid, amopopr, amopstrategy) 
-   SELECT am.oid, opcl.oid, c.opoid, 4
-   FROM pg_am am, pg_opclass opcl, rt_ops_tmp c
-   WHERE amname = 'gist' and opcname = 'gist_box_ops' 
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr) 
+   SELECT opcl.oid, 4, false, c.opoid
+   FROM pg_opclass opcl, rt_ops_tmp c
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_box_ops' 
       and c.oprname = '&>';
 
 -- box_right
-INSERT INTO pg_amop (amopid, amopclaid, amopopr, amopstrategy)
-   SELECT am.oid, opcl.oid, c.opoid, 5
-   FROM pg_am am, pg_opclass opcl, rt_ops_tmp c
-   WHERE amname = 'gist' and opcname = 'gist_box_ops' 
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+   SELECT opcl.oid, 5, false, c.opoid
+   FROM pg_opclass opcl, rt_ops_tmp c
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_box_ops' 
       and c.oprname = '>>';
 
 -- box_same
-INSERT INTO pg_amop (amopid, amopclaid, amopopr, amopstrategy) 
-   SELECT am.oid, opcl.oid, c.opoid, 6
-   FROM pg_am am, pg_opclass opcl, rt_ops_tmp c
-   WHERE amname = 'gist' and opcname = 'gist_box_ops' 
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr) 
+   SELECT opcl.oid, 6, false, c.opoid
+   FROM pg_opclass opcl, rt_ops_tmp c
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_box_ops' 
       and c.oprname = '~=';
 
 -- box_contains
-INSERT INTO pg_amop (amopid, amopclaid, amopopr, amopstrategy)
-   SELECT am.oid, opcl.oid, c.opoid, 7
-   FROM pg_am am, pg_opclass opcl, rt_ops_tmp c
-   WHERE amname = 'gist' and opcname = 'gist_box_ops' 
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+   SELECT opcl.oid, 7, false, c.opoid
+   FROM pg_opclass opcl, rt_ops_tmp c
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_box_ops' 
       and c.oprname = '~';
 
 -- box_contained
-INSERT INTO pg_amop (amopid, amopclaid, amopopr, amopstrategy)
-   SELECT am.oid, opcl.oid, c.opoid, 8
-   FROM pg_am am, pg_opclass opcl, rt_ops_tmp c
-   WHERE amname = 'gist' and opcname = 'gist_box_ops' 
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+   SELECT opcl.oid, 8, false, c.opoid
+   FROM pg_opclass opcl, rt_ops_tmp c
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_box_ops' 
       and c.oprname = '@';
 
 DROP table rt_ops_tmp;
 
 -- add the entries to amproc for the support methods
 -- note the amprocnum numbers associated with each are specific!
-INSERT INTO pg_amproc (amid, amopclaid, amproc, amprocnum)
-   SELECT am.oid, opcl.oid, pro.oid, 1
-   FROM pg_am am, pg_opclass opcl, pg_proc pro
-   WHERE  amname = 'gist' and opcname = 'gist_box_ops'
+
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 1, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_box_ops'
       and proname = 'gbox_consistent';
 
-INSERT INTO pg_amproc (amid, amopclaid, amproc, amprocnum)
-   SELECT am.oid, opcl.oid, pro.oid, 2
-   FROM pg_am am, pg_opclass opcl, pg_proc pro
-   WHERE  amname = 'gist' and opcname = 'gist_box_ops'
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 2, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_box_ops'
       and proname = 'gbox_union';
 
-INSERT INTO pg_amproc (amid, amopclaid, amproc, amprocnum)
-   SELECT am.oid, opcl.oid, pro.oid, 3
-   FROM pg_am am, pg_opclass opcl, pg_proc pro
-   WHERE  amname = 'gist' and opcname = 'gist_box_ops'
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 3, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_box_ops'
       and proname = 'gbox_compress';
 
-INSERT INTO pg_amproc (amid, amopclaid, amproc, amprocnum)
-   SELECT am.oid, opcl.oid, pro.oid, 4
-   FROM pg_am am, pg_opclass opcl, pg_proc pro
-   WHERE  amname = 'gist' and opcname = 'gist_box_ops'
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 4, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_box_ops'
       and proname = 'rtree_decompress';
 
-INSERT INTO pg_amproc (amid, amopclaid, amproc, amprocnum)
-   SELECT am.oid, opcl.oid, pro.oid, 5
-   FROM pg_am am, pg_opclass opcl, pg_proc pro
-   WHERE  amname = 'gist' and opcname = 'gist_box_ops'
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 5, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_box_ops'
       and proname = 'gbox_penalty';
 
-INSERT INTO pg_amproc (amid, amopclaid, amproc, amprocnum)
-   SELECT am.oid, opcl.oid, pro.oid, 6
-   FROM pg_am am, pg_opclass opcl, pg_proc pro
-   WHERE  amname = 'gist' and opcname = 'gist_box_ops'
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 6, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_box_ops'
       and proname = 'gbox_picksplit';
 
-INSERT INTO pg_amproc (amid, amopclaid, amproc, amprocnum)
-   SELECT am.oid, opcl.oid, pro.oid, 7
-   FROM pg_am am, pg_opclass opcl, pg_proc pro
-   WHERE  amname = 'gist' and opcname = 'gist_box_ops'
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 7, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_box_ops'
       and proname = 'gbox_same';
 
 --
@@ -160,124 +191,155 @@ create function gpoly_union(bytea, opaque) returns opaque as 'MODULE_PATHNAME' l
 
 create function gpoly_same(opaque, opaque, opaque) returns opaque as 'MODULE_PATHNAME' language 'C';
 
--- add a new opclass
---INSERT INTO pg_opclass (opcname, opcdeftype)
---   SELECT 'gist_poly_ops', oid
---   FROM pg_type
---   WHERE typname = 'polygon';
-INSERT INTO pg_opclass (opcname, opcdeftype) values ( 'gist_poly_ops', 0 );
-
---SELECT oid, opcname FROM pg_opclass WHERE opcname = 'gist_poly_ops';
+-- add a new opclass (non-default)
+INSERT INTO pg_opclass (opcamid, opcname, opcintype, opcdefault, opckeytype)
+    VALUES (
+        (SELECT oid FROM pg_am WHERE amname = 'gist'),
+        'gist_poly_ops',
+        (SELECT oid FROM pg_type WHERE typname = 'polygon'),
+        false,
+        0);
 
 -- get the comparators for polygons and store them in a tmp table
 -- hack for 757 (poly_contain_pt) Teodor
 SELECT o.oid AS opoid, o.oprname
-INTO TABLE rt_ops_tmp
+INTO TEMP TABLE rt_ops_tmp
 FROM pg_operator o, pg_type t
 WHERE o.oprleft = t.oid and o.oid <> 757
    and t.typname = 'polygon';
 
 -- using the tmp table, generate the amop entries 
 -- poly_left
-INSERT INTO pg_amop (amopid, amopclaid, amopopr, amopstrategy) 
-   SELECT am.oid, opcl.oid, c.opoid, 1
-   FROM pg_am am, pg_opclass opcl, rt_ops_tmp c
-   WHERE amname = 'gist' and opcname = 'gist_poly_ops' 
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr) 
+   SELECT opcl.oid, 1, false, c.opoid
+   FROM pg_opclass opcl, rt_ops_tmp c
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_poly_ops' 
       and c.oprname = '<<';
 
 -- poly_overleft
-INSERT INTO pg_amop (amopid, amopclaid, amopopr, amopstrategy) 
-   SELECT am.oid, opcl.oid, c.opoid, 2
-   FROM pg_am am, pg_opclass opcl, rt_ops_tmp c
-   WHERE amname = 'gist' and opcname = 'gist_poly_ops' 
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr) 
+   SELECT opcl.oid, 2, false, c.opoid
+   FROM pg_opclass opcl, rt_ops_tmp c
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_poly_ops' 
       and c.oprname = '&<';
 
 -- poly_overlap
-INSERT INTO pg_amop (amopid, amopclaid, amopopr, amopstrategy) 
-   SELECT am.oid, opcl.oid, c.opoid, 3
-   FROM pg_am am, pg_opclass opcl, rt_ops_tmp c
-   WHERE amname = 'gist' and opcname = 'gist_poly_ops' 
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr) 
+   SELECT opcl.oid, 3, false, c.opoid
+   FROM pg_opclass opcl, rt_ops_tmp c
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_poly_ops' 
       and c.oprname = '&&';
 
 -- poly_overright
-INSERT INTO pg_amop (amopid, amopclaid, amopopr, amopstrategy) 
-   SELECT am.oid, opcl.oid, c.opoid, 4
-   FROM pg_am am, pg_opclass opcl, rt_ops_tmp c
-   WHERE amname = 'gist' and opcname = 'gist_poly_ops' 
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr) 
+   SELECT opcl.oid, 4, false, c.opoid
+   FROM pg_opclass opcl, rt_ops_tmp c
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_poly_ops' 
       and c.oprname = '&>';
 
 -- poly_right
-INSERT INTO pg_amop (amopid, amopclaid, amopopr, amopstrategy)
-   SELECT am.oid, opcl.oid, c.opoid, 5
-   FROM pg_am am, pg_opclass opcl, rt_ops_tmp c
-   WHERE amname = 'gist' and opcname = 'gist_poly_ops' 
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+   SELECT opcl.oid, 5, false, c.opoid
+   FROM pg_opclass opcl, rt_ops_tmp c
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_poly_ops' 
       and c.oprname = '>>';
 
 -- poly_same
-INSERT INTO pg_amop (amopid, amopclaid, amopopr, amopstrategy) 
-   SELECT am.oid, opcl.oid, c.opoid, 6
-   FROM pg_am am, pg_opclass opcl, rt_ops_tmp c
-   WHERE amname = 'gist' and opcname = 'gist_poly_ops' 
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr) 
+   SELECT opcl.oid, 6, false, c.opoid
+   FROM pg_opclass opcl, rt_ops_tmp c
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_poly_ops' 
       and c.oprname = '~=';
 
 -- poly_contains
-INSERT INTO pg_amop (amopid, amopclaid, amopopr, amopstrategy)
-   SELECT am.oid, opcl.oid, c.opoid, 7
-   FROM pg_am am, pg_opclass opcl, rt_ops_tmp c
-   WHERE amname = 'gist' and opcname = 'gist_poly_ops' 
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+   SELECT opcl.oid, 7, false, c.opoid
+   FROM pg_opclass opcl, rt_ops_tmp c
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_poly_ops' 
       and c.oprname = '~';
 
 -- poly_contained
-INSERT INTO pg_amop (amopid, amopclaid, amopopr, amopstrategy)
-   SELECT am.oid, opcl.oid, c.opoid, 8
-   FROM pg_am am, pg_opclass opcl, rt_ops_tmp c
-   WHERE amname = 'gist' and opcname = 'gist_poly_ops' 
+INSERT INTO pg_amop (amopclaid, amopstrategy, amopreqcheck, amopopr)
+   SELECT opcl.oid, 8, false, c.opoid
+   FROM pg_opclass opcl, rt_ops_tmp c
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_poly_ops' 
       and c.oprname = '@';
 
 DROP table rt_ops_tmp;
 
 -- add the entries to amproc for the support methods
 -- note the amprocnum numbers associated with each are specific!
-INSERT INTO pg_amproc (amid, amopclaid, amproc, amprocnum)
-   SELECT am.oid, opcl.oid, pro.oid, 1
-   FROM pg_am am, pg_opclass opcl, pg_proc pro
-   WHERE  amname = 'gist' and opcname = 'gist_poly_ops'
+
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 1, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_poly_ops'
       and proname = 'gpoly_consistent';
 
-INSERT INTO pg_amproc (amid, amopclaid, amproc, amprocnum)
-   SELECT am.oid, opcl.oid, pro.oid, 2
-   FROM pg_am am, pg_opclass opcl, pg_proc pro
-   WHERE  amname = 'gist' and opcname = 'gist_poly_ops'
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 2, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_poly_ops'
       and proname = 'gpoly_union';
 
-INSERT INTO pg_amproc (amid, amopclaid, amproc, amprocnum)
-   SELECT am.oid, opcl.oid, pro.oid, 3
-   FROM pg_am am, pg_opclass opcl, pg_proc pro
-   WHERE  amname = 'gist' and opcname = 'gist_poly_ops'
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 3, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_poly_ops'
       and proname = 'gpoly_compress';
 
-INSERT INTO pg_amproc (amid, amopclaid, amproc, amprocnum)
-   SELECT am.oid, opcl.oid, pro.oid, 4
-   FROM pg_am am, pg_opclass opcl, pg_proc pro
-   WHERE  amname = 'gist' and opcname = 'gist_poly_ops'
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 4, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_poly_ops'
       and proname = 'rtree_decompress';
 
-INSERT INTO pg_amproc (amid, amopclaid, amproc, amprocnum)
-   SELECT am.oid, opcl.oid, pro.oid, 5
-   FROM pg_am am, pg_opclass opcl, pg_proc pro
-   WHERE  amname = 'gist' and opcname = 'gist_poly_ops'
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 5, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_poly_ops'
       and proname = 'gpoly_penalty';
 
-INSERT INTO pg_amproc (amid, amopclaid, amproc, amprocnum)
-   SELECT am.oid, opcl.oid, pro.oid, 6
-   FROM pg_am am, pg_opclass opcl, pg_proc pro
-   WHERE  amname = 'gist' and opcname = 'gist_poly_ops'
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 6, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_poly_ops'
       and proname = 'gpoly_picksplit';
 
-INSERT INTO pg_amproc (amid, amopclaid, amproc, amprocnum)
-   SELECT am.oid, opcl.oid, pro.oid, 7
-   FROM pg_am am, pg_opclass opcl, pg_proc pro
-   WHERE  amname = 'gist' and opcname = 'gist_poly_ops'
+INSERT INTO pg_amproc (amopclaid, amprocnum, amproc)
+   SELECT opcl.oid, 7, pro.oid
+   FROM pg_opclass opcl, pg_proc pro
+   WHERE
+      opcamid = (SELECT oid FROM pg_am WHERE amname = 'gist')
+      and opcname = 'gist_poly_ops'
       and proname = 'gpoly_same';
 
 end transaction;