blanks, in hopes of reducing the surprise factor for newbies. Remove
redundant operators for VARCHAR (it depends wholly on TEXT operations now).
Clean up resolution of ambiguous operators/functions to avoid surprising
choices for domains: domains are treated as equivalent to their base types
and binary-coercibility is no longer considered a preference item when
choosing among multiple operators/functions. IsBinaryCoercible now correctly
reflects the notion that you need *only* relabel the type to get from type
A to type B: that is, a domain is binary-coercible to its base type, but
not vice versa. Various marginal cleanup, including merging the essentially
duplicate resolution code in parse_func.c and parse_oper.c. Improve opr_sanity
regression test to understand about binary compatibility (using pg_cast),
and fix a couple of small errors in the catalogs revealed thereby.
Restructure "special operator" handling to fetch operators via index opclasses
rather than hardwiring assumptions about names (cleans up the pattern_ops
stuff a little).
only remnant of this failed experiment is that the server will take
SET AUTOCOMMIT TO ON. Still TODO: provide some client-side autocommit
logic in libpq.
dropped. The simplest fix for INSERT/UPDATE cases turns out to be for
preptlist.c to insert NULLs of a known-good type (I used INT4) rather
than making them match the deleted column's type. Since the representation
of NULL is actually datatype-independent, this should work fine.
I also re-reverted the patch to disable the use_physical_tlist optimization
in the presence of dropped columns. It still doesn't look worth the
trouble to be smarter, if there are no other bugs to fix.
Added a regression test to catch future problems in this area.
rewritten and the protocol is changed, but most elog calls are still
elog calls. Also, we need to contemplate mechanisms for controlling
all this functionality --- eg, how much stuff should appear in the
postmaster log? And what API should libpq expose for it?
have length words. COPY OUT reimplemented per new protocol: it doesn't
need \. anymore, thank goodness. COPY BINARY to/from frontend works,
at least as far as the backend is concerned --- libpq's PQgetline API
is not up to snuff, and will have to be replaced with something that is
null-safe. libpq uses message length words for performance improvement
(no cycles wasted rescanning long messages), but not yet for error
recovery.
with variable-width fields. No more truncation of long user names.
Also, libpq can now send its environment-variable-driven SET commands
as part of the startup packet, saving round trips to server.
expressions, ARRAY(sub-SELECT) expressions, some array functions.
Polymorphic functions using ANYARRAY/ANYELEMENT argument and return
types. Some regression tests in place, documentation is lacking.
Joe Conway, with some kibitzing from Tom Lane.
on UPDATE.
This get's rid of the long standing annoyance that updating a row
that has foreign keys locks all the referenced rows even if the
foreign key values do not change.
The trick is to actually do a check identical to NO ACTION after an
eventually done UPDATE in the SET DEFAULT case. Since a SET DEFAULT
operation should have moved referencing rows to a new "home", a following
NO ACTION check can only fail if the column defaults of the referencing
table resulted in the key we actually deleted. Thanks to Stephan.
Jan
(materialization into a tuple store) discussed on pgsql-hackers earlier.
I've updated the documentation and the regression tests.
Notes on the implementation:
- I needed to change the tuple store API slightly -- it assumes that it
won't be used to hold data across transaction boundaries, so the temp
files that it uses for on-disk storage are automatically reclaimed at
end-of-transaction. I added a flag to tuplestore_begin_heap() to control
this behavior. Is changing the tuple store API in this fashion OK?
- in order to store executor results in a tuple store, I added a new
CommandDest. This works well for the most part, with one exception: the
current DestFunction API doesn't provide enough information to allow the
Executor to store results into an arbitrary tuple store (where the
particular tuple store to use is chosen by the call site of
ExecutorRun). To workaround this, I've temporarily hacked up a solution
that works, but is not ideal: since the receiveTuple DestFunction is
passed the portal name, we can use that to lookup the Portal data
structure for the cursor and then use that to get at the tuple store the
Portal is using. This unnecessarily ties the Portal code with the
tupleReceiver code, but it works...
The proper fix for this is probably to change the DestFunction API --
Tom suggested passing the full QueryDesc to the receiveTuple function.
In that case, callers of ExecutorRun could "subclass" QueryDesc to add
any additional fields that their particular CommandDest needed to get
access to. This approach would work, but I'd like to think about it for
a little bit longer before deciding which route to go. In the mean time,
the code works fine, so I don't think a fix is urgent.
- (semi-related) I added a NO SCROLL keyword to DECLARE CURSOR, and
adjusted the behavior of SCROLL in accordance with the discussion on
-hackers.
- (unrelated) Cleaned up some SGML markup in sql.sgml, copy.sgml
Neil Conway
them as arrays of the internal datatype. This requires treating the
stavalues columns as 'anyarray' rather than 'text[]', which is not 100%
kosher but seems to work fine for the purposes we need for pg_statistic.
Perhaps in the future 'anyarray' will be allowed more generally.
some of the algorithms for higher functions. I see about a factor of ten
speedup on the 'numeric' regression test, but it's unlikely that that test
is representative of real-world applications.
initdb forced due to change of on-disk representation for NUMERIC.
Add ALTER SEQUENCE to modify min/max/increment/cache/cycle values
Also updated create sequence docs to mention NO MINVALUE, & NO MAXVALUE.
New Files:
doc/src/sgml/ref/alter_sequence.sgml
src/test/regress/expected/sequence.out
src/test/regress/sql/sequence.sql
ALTER SEQUENCE is NOT transactional. It behaves similarly to setval().
It matches the proposed SQL200N spec, as well as Oracle in most ways --
Oracle lacks RESTART WITH for some strange reason.
--
Rod Taylor <rbt@rbt.ca>
what is capable using integer-datatime timestamps. It does attempt
to exercise the maximum allowable timestamp range.
Also is a small error check when converting a timestamp from external
to internal format that prevents out of range timestamps from being
entered.
Files patched:
Index: src/backend/utils/adt/timestamp.c
Added range check to prevent out of range timestamps
from being used.
Index: src/test/regress/sql/horology.sql
Index: src/test/regress/expected/horology-no-DST-before-1970.out
Index: src/test/regress/expected/horology-solaris-1947.out
Limited range of timestamps being checked to
Jan 1, 4713 BC to Dec 31, 294276
In creating this patch, I have seen some definite problems with integer
timestamps and how they react when used near their limits. For example,
the following statement gives the correct result:
SELECT timestamp without time zone 'Jan 1, 4713 BC'
+ interval '109203489 days' AS "Dec 31, 294276";
However, this statement which is the logical inverse of the above
gives incorrect results:
SELECT timestamp without time zone '12/31/294276'
- timestamp without time zone 'Jan 1, 4713 BC' AS "109203489 Days";
John Cochran
division and modulo functions, to avoid problems on OS X (which fails to
trap 0 divide at all) and Windows (which traps it in some bizarre
nonstandard fashion). Standardize on 'division by zero' as the one true
spelling of this error message. Add regression tests as suggested by
Neil Conway.
RelOid_pg_class, and transaction locks XactLockTableId. RelId is renamed
to objId.
- LockObject() and UnlockObject() functions created, and their use
sprinkled throughout the code to do descent locking for domains and
types. They accept lock modes AccessShare and AccessExclusive, as we
only really need a 'read' and 'write' lock at the moment. Most locking
cases are held until the end of the transaction.
This fixes the cases Tom mentioned earlier in regards to locking with
Domains. If the patch is good, I'll work on cleaning up issues with
other database objects that have this problem (most of them).
Rod Taylor
functions which limited the maximum date for a timestamp to AD 1465001.
The new limit is AD 5874897.
The files affected are:
doc/src/sgml/datatype.sgml:
Documentation change due to patch. Included is a notice about
the reduced range when using an eight-byte integer for timestamps.
src/backend/utils/adt/datetime.c:
Replacement functions for j2date() and date2j() functions.
src/include/utils/datetime.h:
Corrected a bug with the limit on the earliest possible date,
Nov 23,-4713 has a Julian day count of -1. The earliest possible
date should be Nov 24, -4713 with a day count of 0.
src/test/regress/expected/horology-no-DST-before-1970.out:
src/test/regress/expected/horology-solaris-1947.out:
src/test/regress/expected/horology.out:
Copies of expected output for regression testing.
Note: Only horology.out has been physically tested. I do not have access
to a Solaris box and I don't know how to provoke the "pre-1970" test.
src/test/regress/sql/horology.sql:
Added some test cases to check extended range.
John Cochran
of the containing query (which really can only happen in a rule context).
Per example from Brandon Craig Rhodes. Also, make the error message
more specific for the similar case with sub-select in FROM. The revised
coding should be easier to adapt to SQL99's LATERAL(), when we get around
to supporting that.
takes two parameters, an OID x and an integer y, and returns "true" with
probability 1/y (the OID argument is ignored). This can be useful -- for
example, it can be used to select a random sampling of the rows in a
table (which is what the "random" regression test uses it for).
This patch removes that function, because it was old and messy. The old
function had the following problems:
- it was undocumented
- it was poorly named
- it was designed to workaround an optimizer bug that no longer exists
(the OID argument is to ensure that the optimizer won't optimize away
calls to the function; AFAIK marking the function as 'volatile' suffices
nowadays)
- it used a different random-number generation technique than the other
PSRNG-related functions in the backend do (it called random() like they
do, but it had its own logic for setting a set and deciding when to
reseed the RNG).
Ok, this patch removes oidrand(), oidsrand(), and userfntest(), and
improves the SGML docs a little bit (un-commenting the setseed()
documentation).
Neil Conway
On Wed, 2003-01-08 at 21:59, Christopher Kings-Lynne wrote:
> I agree. I want to remove OIDs from heaps of our tables when we go to 7.3.
> I'd rather not have to do it in the dump due to down time.
Rod Taylor <rbt@rbt.ca>
constraints appearing in outer-join qualification clauses are restricted
as to when and where they can be pushed down. Add regression test
to catch future errors in this area.
startup, not in the parser; this allows ALTER DOMAIN to work correctly
with domain constraint operations stored in rules. Rod Taylor;
code review by Tom Lane.
for type 'time without time zone', as we already did for type
'timestamp without time zone'. This patch was proposed by Tom Lockhart
on 7-Nov-02, but he never got around to applying it. Adjust regression
tests and documentation to match.
passed to join selectivity estimators. Make use of this in eqjoinsel
to derive non-bogus selectivity for IN clauses. Further tweaking of
cost estimation for IN.
initdb forced because of pg_proc.h changes.
Try to model the effect of rescanning input tuples in mergejoins;
account for JOIN_IN short-circuiting where appropriate. Also, recognize
that mergejoin and hashjoin clauses may now be more than single operator
calls, so we have to charge appropriate execution costs.
necessarily following the JOIN syntax to develop the query plan. The old
behavior is still available by setting GUC variable JOIN_COLLAPSE_LIMIT
to 1. Also create a GUC variable FROM_COLLAPSE_LIMIT to control the
similar decision about when to collapse sub-SELECT lists into their parent
lists. (This behavior existed already, but the limit was always
GEQO_THRESHOLD/2; now it's separately adjustable.)
There are two implementation techniques: the executor understands a new
JOIN_IN jointype, which emits at most one matching row per left-hand row,
or the result of the IN's sub-select can be fed through a DISTINCT filter
and then joined as an ordinary relation.
Along the way, some minor code cleanup in the optimizer; notably, break
out most of the jointree-rearrangement preprocessing in planner.c and
put it in a new file prep/prepjointree.c.
datetime token tables. Even more embarrassing, the regression tests
revealed some of the problems --- but evidently the bogus output wasn't
questioned. Add code to postmaster startup to directly check the tables
for correct ordering, in hopes of not being embarrassed like this again.
containing a volatile function), rather than only on 'Var = Var' clauses
as before. This makes it practical to do flatten_join_alias_vars at the
start of planning, which in turn eliminates a bunch of klugery inside the
planner to deal with alias vars. As a free side effect, we now detect
implied equality of non-Var expressions; for example in
SELECT ... WHERE a.x = b.y and b.y = 42
we will deduce a.x = 42 and use that as a restriction qual on a. Also,
we can remove the restriction introduced 12/5/02 to prevent pullup of
subqueries whose targetlists contain sublinks.
Still TODO: make statistical estimation routines in selfuncs.c and costsize.c
smarter about expressions that are more complex than plain Vars. The need
for this is considerably greater now that we have to be able to estimate
the suitability of merge and hash join techniques on such expressions.
match parent table. This used to work, but was broken in 7.3 by
rearrangement of code that handles targetlist sorting. Add a regression
test to catch future breakage.