quite the same way that transformInsertStatement does, so that an expression
could be accepted by CREATE TABLE and then fail when used. Also, put back
check that CONSTRAINT expressions must yield boolean...
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.
Implements the CREATE CONSTRAINT TRIGGER and SET CONSTRAINTS commands.
TODO:
Generic builtin trigger procedures
Automatic execution of appropriate CREATE CONSTRAINT... at CREATE TABLE
Support of new trigger type in pg_dump
Swapping of huge # of events to disk
Jan
* Buffer refcount cleanup (per my "progress report" to pghackers, 9/22).
* Add links to backend PROC structs to sinval's array of per-backend info,
and use these links for routines that need to check the state of all
backends (rather than the slow, complicated search of the ShmemIndex
hashtable that was used before). Add databaseOID to PROC structs.
* Use this to implement an interlock that prevents DESTROY DATABASE of
a database containing running backends. (It's a little tricky to prevent
a concurrently-starting backend from getting in there, since the new
backend is not able to lock anything at the time it tries to look up
its database in pg_database. My solution is to recheck that the DB is
OK at the end of InitPostgres. It may not be a 100% solution, but it's
a lot better than no interlock at all...)
* In ALTER TABLE RENAME, flush buffers for the relation before doing the
rename of the physical files, to ensure we don't get failures later from
mdblindwrt().
* Update TRUNCATE patch so that it actually compiles against current
sources :-(.
You should do "make clean all" after pulling these changes.
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.
We can't support these properly, since once the relation's physical files
are unlinked, there's no way to roll back the transaction. I suppose
we could postpone the unlink till transaction commit, but then what of
BEGIN; DROP TABLE foo; CREATE TABLE foo; ?
The code does allow dropping a table/index created in the current
transaction block, however, since the post-abort state would be that
the table doesn't exist anyway.
segments, and my indexes had 3(Yes, it DOES work!).
DROP TABLE removed ALL segments from the table, but only the main index
segment.
So it looks like removing the table itself is using mdunlink in md.c,
while removing indexes uses FileNameUnlink() which only unlinks 1 file.
As far as I can tell, calling FileNameUnlink() and mdunlink() is basically
the same, except mdunlink() deletes any extra segments.
I've done some testing and it seems to work. It also passes regression
tests(except float8, geometry and rules, but that's normal).
If this patch is right, this fixes all known multi-segment problems on
Linux.
Ole Gjerde
lists are now plain old garden-variety Lists, allocated with palloc,
rather than specialized expansible-array data allocated with malloc.
This substantially simplifies their handling and eliminates several
sources of memory leakage.
Several basic types of erroneous queries (syntax error, attempt to
insert a duplicate key into a unique index) now demonstrably leak
zero bytes per query.
relation, rather than zeroes. This prevents the optimizer from making
foolish choices (ie, using nested-loop plans) on never-yet-vacuumed tables.
This is a hack, of course. Keeping accurate track of these statistics
would be a cleaner solution, but it's far from clear that it'd be worth
the cost of doing so. In any case we're not going to do that for 6.5.
In the meantime, this quick hack provides a useful performance improvement
in the regression tests and in many real-world scenarios.
not-yet-defined operator in commutator, negator, etc links. This is
necessary in order to ensure that a pg_dump dump of user-defined operators
can be reloaded. There may still be a bug lurking here, because it's
provoking a 'Buffer Leak' notice message in one case. See my mail to
pgsql-hackers.
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.
Tom Lane
Vadim B. Mikheev
Jan Wieck
Bruce Momjian
Thomas G. Lockhart
Marc G. Fournier