so that fetching an attribute value needs only one SearchSysCacheTuple call
instead of two redundant searches. This speeds up a large SELECT by about
ten percent, and probably will help GROUP BY and SELECT DISTINCT too.
After some playing with gdb I found that in printtup() there is a non null
attribute with typeinfo->attrs[i]->atttypid = 0 (invalid oid). Unfortunately
attibutes with invalid type are neither printed nor marked as null, and this
explains why psql doesn't get all the expected data.
So I made this patch to printtup():
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;
As Bruce mentioned, this is due to the conflict among changes we made.
Included patches should fix the problem(I changed all MB to
MULTIBYTE). Please let me know if you have further problem.
P.S. I did not include pathces to configure and gram.c to save the
file size(configure.in and gram.y modified).
I have implemented a framework of encoding translation between the
backend and the frontend. Also I have added a new variable setting
command:
SET CLIENT_ENCODING TO 'encoding';
Other features include:
Latin1 support more 8 bit cleaness
See doc/README.mb for more details. Note that the pacthes are
against May 30 snapshot.
Tatsuo Ishii
Attached you'll find a (big) patch that fixes make dep and make
depend in all Makefiles where I found it to be appropriate.
It also removes the dependency in Makefile.global for NAMEDATALEN
and OIDNAMELEN by making backend/catalog/genbki.sh and bin/initdb/initdb.sh
a little smarter.
This no longer requires initdb.sh that is turned into initdb with
a sed script when installing Postgres, hence initdb.sh should be
renamed to initdb (after the patch has been applied :-) )
This patch is against the 6.3 sources, as it took a while to
complete.
Please review and apply,
Cheers,
Jeroen van Vianen
1. Remove the char2, char4, char8 and char16 types from postgresql
2. Change references of char16 to name in the regression tests.
3. Rename the char16.sql regression test to name.sql. 4. Modify
the regression test scripts and outputs to match up.
Might require new regression.{SYSTEM} files...
Darren King
select from a table with attrs (a int, b char(20))
crashed in bpcharout() (palloc of -1 bytes). But a table
with attrs (a int, b varchar(20)) worked.
From: Jan Wieck <jwieck@debis.com>
varchar length.
Cleans up code so attlen is always length.
Removed varchar() hack added earlier.
Will fix bug in selecting varchar() fields, and varchar() can be
variable length.
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.
Essentially, this cleans things up so that if PORTNAME isn't defined (I'm
working on getting rid of it for FreeBSD, at least, to see if its possible)
none of the PORTNAME related stuff gets passed around.
Had a little bit of -I related redundancy as well
Reply-To: hackers@hub.org, Dan McGuirk <mcguirk@indirect.com>
To: hackers@hub.org
Subject: [HACKERS] tmin writeback optimization
I was doing some profiling of the backend, and noticed that during a certain
benchmark I was running somewhere between 30% and 75% of the backend's CPU
time was being spent in calls to TransactionIdDidCommit() from
HeapTupleSatisfiesNow() or HeapTupleSatisfiesItself() to determine that
changed rows' transactions had in fact been committed even though the rows'
tmin values had not yet been set.
When a query looks at a given row, it needs to figure out whether the
transaction that changed the row has been committed and hence it should pay
attention to the row, or whether on the other hand the transaction is still
in progress or has been aborted and hence the row should be ignored. If
a tmin value is set, it is known definitively that the row's transaction
has been committed. However, if tmin is not set, the transaction
referred to in xmin must be looked up in pg_log, and this is what the
backend was spending a lot of time doing during my benchmark.
So, implementing a method suggested by Vadim, I created the following
patch that, the first time a query finds a committed row whose tmin value
is not set, sets it, and marks the buffer where the row is stored as
dirty. (It works for tmax, too.) This doesn't result in the boost in
real time performance I was hoping for, however it does decrease backend
CPU usage by up to two-thirds in certain situations, so it could be
rather beneficial in high-concurrency settings.
Subject: [HACKERS] linux/alpha patches
These patches lay the groundwork for a Linux/Alpha port. The port doesn't
actually work unless you tweak the linker to put all the pointers in the
first 32 bits of the address space, but it's at least a start. It
implements the test-and-set instruction in Alpha assembly, and also fixes
a lot of pointer-to-integer conversions, which is probably good anyway.
I found another bug in btree index. Looking at the code it seems that NULL
keys are never used to build or scan a btree index (see the explain commands
in the example). However this is not the case when a null key is retrieved
in an outer loop of a join select and used in an index scan of an inner loop.
This bug causes at least three kinds of problems:
1) the backend crashes when it tries to compare a text string with a null.
2) it is not possible to find tuples with null keys in a join.
3) null is considered equal to 0 when the datum is passed by value, see
the last query.
Submitted by: Massimo Dal Zotto <dz@cs.unitn.it>
- Added the header access/heapam.h.
- Changed all instances of "length" to "data_length" to quiet
the compiler.
- initialized a few variables. The compiler couldn't see that
the code guaranteed that these would be initialized before
being dereferenced. If anyone wants to check my work follow
the usage of these variables and make sure that this true
and wasn't actually a bug in the original code.
- added a missing break statement to a default case. This
was a benign error but bad style.
- layed out heap_sysattrlen differently. I think this way
makes the structure of the code crystal clear. There should
be no actual difference in the actual behaviour of the code.
Submitted by: darcy@druid.druid.com (D'Arcy J.M. Cain)
Here's a small patch that my run-time checker whines about
incessantly. The justification for the patch is along the
lines of passing a NULL is allowed if you have an
arguement that is a *POINTER* to something, but if
the arguement is an array reference, it's not really
a "pointer", so it can't be NULL.
If you question this, I refer you to
<URL:http://www.va.pubnix.com/staff/djm/lore/arrays-are-not-pointers>
Anyways, here's the patch:
-Kurt
Submitted by: "Kurt J. Lidl" <lidl@va.pubnix.com>