is used to find start scan position of Indexscan-s.
To speed up finding scan start position,I have changed
_bt_first() to use as many keys as possible.
I'll attach the patch here.
Regards.
Hiroshi Inoue
indexes.
1. Index Scan using plural indexids never scan backward
as to the order of indexids.
2. The cursor using Index scan is not usable after moving
past the end.
This patch solves above bugs.
Moreover the change of _bt_first() would be useful to extend
ORDER BY patch by Jan Wieck for all descending order cases.
Hiroshi Inoue
no longer returns buffer pointer, can be gotten from scan;
descriptor; bootstrap can create multi-key indexes;
pg_procname index now is multi-key index; oidint2, oidint4, oidname
are gone (must be removed from regression tests); use System Cache
rather than sequential scan in many places; heap_modifytuple no
longer takes buffer parameter; remove unused buffer parameter in
a few other functions; oid8 is not index-able; remove some use of
single-character variable names; cleanup Buffer variables usage
and scan descriptor looping; cleaned up allocation and freeing of
tuples; 18k lines of diff;
1. Removes the unnecessary "#define AbcRegProcedure 123"'s from
pg_proc.h.
2. Changes those #defines to use the names already defined in
fmgr.h.
3. Forces the make of fmgr.h in backend/Makefile instead of having
it
made as a dependency in access/common/Makefile *hack*hack*hack*
4. Rearranged the #includes to a less helter-skelter arrangement,
also
changing <file.h> to "file.h" to signify a non-system header.
5. Removed "pg_proc.h" from files where its only purpose was for
the
#defines removed in item #1.
6. Added "fmgr.h" to each file changed for completeness sake.
Turns out that #6 was not necessary for some files because fmgr.h
was being included in a roundabout way SIX levels deep by the first
include.
"access/genam.h"
->"access/relscan.h"
->"utils/rel.h"
->"access/strat.h"
->"access/skey.h"
->"fmgr.h"
So adding fmgr.h really didn't add anything to the compile, hopefully
just made it clearer to the programmer.
S Darren.
Patch by: wieck@sapserv.debis.de (Jan Wieck)
One of the design rules of PostgreSQL is extensibility. And
to follow this rule means (at least for me) that there should
not only be a builtin PL. Instead I would prefer a defined
interface for PL implemetations.
index tuple (logical position within A LEVEL). bti_oid & bti_dummy
taken off from BTItemData.
2. Fix for multi-column indices (nbtsearch.c):
_bt_binsrch() - for searches on internal pages having keysize <
number of attrs we point at the last item < the scankey, not at the
first item = the scankey;
_bt_moveright() - if keysize < number of attrs we compare scankey with
_last_ item on current page to decide should we move right or
not.
Actually required by multi-column indices support.
We still don't use btree for 'A is (not) null', but
now btree keep items with NULL attrs using single rule
for placing/finding items on pages:
NULLs greater NOT_NULLs and NULL = NULL.
+ Bulkload code (nbtsort.c) support for multi-column indices
building and NULLs.
+ Fix for btendscan()->pfree(scanopaque) from Chris Dunlop.
> INDEXED searches in some cases DO NOT WORK.
> Although simple search expressions (i.e. with a constant value on
> the right side of an operator) work, performing a join (by putting
> a field of some other table on the right side of an operator) produces
> empty output.
> WITHOUT indices, everything works fine.
>
submitted by: "Vadim B. Mikheev" <root@ais.sable.krasnoyarsk.su>