expressions in CREATE TABLE. There is no longer an emasculated expression
syntax for these things; it's full a_expr for constraints, and b_expr
for defaults (unfortunately the fact that NOT NULL is a part of the
column constraint syntax causes a shift/reduce conflict if you try a_expr.
Oh well --- at least parenthesized boolean expressions work now). Also,
stored expression for a column default is not pre-coerced to the column
type; we rely on transformInsertStatement to do that when the default is
actually used. This means "f1 datetime default 'now'" behaves the way
people usually expect it to.
BTW, all the support code is now there to implement ALTER TABLE ADD
CONSTRAINT and ALTER TABLE ADD COLUMN with a default value. I didn't
actually teach ALTER TABLE to call it, but it wouldn't be much work.
additional argument specifying the kind of lock to acquire/release (or
'NoLock' to do no lock processing). Ensure that all relations are locked
with some appropriate lock level before being examined --- this ensures
that relevant shared-inval messages have been processed and should prevent
problems caused by concurrent VACUUM. Fix several bugs having to do with
mismatched increment/decrement of relation ref count and mismatched
heap_open/close (which amounts to the same thing). A bogus ref count on
a relation doesn't matter much *unless* a SI Inval message happens to
arrive at the wrong time, which is probably why we got away with this
sloppiness for so long. Repair missing grab of AccessExclusiveLock in
DROP TABLE, ALTER/RENAME TABLE, etc, as noted by Hiroshi.
Recommend 'make clean all' after pulling this update; I modified the
Relation struct layout slightly.
Will post further discussion to pghackers list shortly.
was rejecting negative attnums as bogus, which of course they are not.
Add code to get_attdisbursion to produce a useful value for OID attribute,
since VACUUM does not store stats for system attributes.
Also, repair bug that's been in eqjoinsel for a long time: it was taking
the max of the two columns' disbursions, whereas it should use the min.
current transaction) are not flushed by shared-cache-inval reset message.
SI reset actually works now, for probably the first time in a long time.
I was able to run initdb and regression tests with a 16-element SI message
array, with a lot of NOTICE: cache state reset messages but no crashes.
real name before doing lookup. We only want to index temp tables by their
real names in the relcache, to ensure there's not more than one relcache
entry for them.
has positive refcount, it is rebuilt from pg_class data. This ensures
that relcache entries will track changes made by other backends. Formerly,
a shared inval report would just be ignored if it happened to arrive while
the relcache entry was in use. Also, fix relcache to reset ref counts
to zero during transaction abort. Finally, change LockRelation() so that
it checks for shared inval reports after obtaining the lock. In this way,
once any kind of lock has been obtained on a rel, we can trust the relcache
entry to be up-to-date.
insight that RelationFlushRelation ought to invoke smgrclose, and that the
way to make that work is to ensure that mdclose doesn't fail if the relation
is already closed (or unlinked, if we are looking at a DROP TABLE). While
I was testing that, I was able to identify several problems that we had
with multiple-segment relations. The system is now able to do initdb and
pass the regression tests with a very small segment size (I had it set to
64Kb per segment for testing). I don't believe that ever worked before.
File descriptor leaks seem to be gone too.
I have partially addressed the concerns we had about mdtruncate(), too.
On a Win32 or NFS filesystem it is not possible to unlink a file that
another backend is holding open, so what md.c now does is to truncate
unwanted files to zero length before trying to unlink them. The other
backends will be forced to close their open files by relation cache
invalidation --- but I think it would take considerable work to make
that happen before vacuum truncates the relation rather than after.
Leaving zero-length files lying around seems a usable compromise.
to save a little bit of backend startup time. This way, the first
backend started after a VACUUM will rebuild the init file with up-to-date
statistics for the critical system indexes.
Ok. I made patches replacing all of "#if FALSE" or "#if 0" to "#ifdef
NOT_USED" for current. I have tested these patches in that the
postgres binaries are identical.
I don't know if this is really related to the initdb problem
discussion (haven't followed it enough). But seems so because
it fixes a damn problem during index tuple insertion on
CREATE TABLE into pg_attribute_relid_attnum_index.
Anyway - this bug was really hard to find. During startup the
relcache reads in some prepared information about index
strategies from a file and then reinitializes the function
pointers inside the scanKey data. But for sake it assumed
single attribute index tuples (hasn't that changed recently).
Thus not all the strategies scanKey entries where initialized
properly, resulting in invalid addresses for the btree
comparision functions.
With the patch at the end the regression tests passed
excellent except for the sanity_check that crashed at vacuum
and the misc test where the select unique1 from onek2 outputs
the two rows in different order.
Jan
if MULTIBYTE is not enabled. So be sure to run initdb.
o these patches are made against the latest source tree (after
Bruce's massive patch, I think) BTW, I noticed that after running
regression, the oid field of pg_type seems disappeared.
regression=> select oid from pg_type; ERROR: attribute
'oid' not found
this happens after the constraints test. This occures with/without
my patches. strange...
o pg_database_mb.h, pg_class_mb.h, pg_attribute_mb.h are no longer
used, and shoud be removed.
o GetDatabaseInfo() in utils/misc/database.c removed (actually in
#ifdef 0). seems nobody uses.
t-ishii@sra.co.jp
