Commit Graph

1158 Commits

Author SHA1 Message Date
2de946be6a Improve the performance of LIKE/regex estimation in non-C locales, by making
make_greater_string() try harder to generate a string that's actually greater
than its input string.  Before we just assumed that making a string that was
memcmp-greater was enough, but it is easy to generate examples where this is
not so when the locale is not C.  Instead, loop until the relevant comparison
function agrees that the generated string is greater than the input.

Unfortunately this is probably not enough to guarantee that the generated
string is greater than all extensions of the input, so we cannot relax the
restriction to C locale for the LIKE/regex index optimization.  But it should
at least improve the odds of getting a useful selectivity estimate in
prefix_selectivity().  Per example from Guillaume Smet.

Backpatch to 8.1, mainly because that's what the complainant is using...
2007-11-07 22:37:24 +00:00
5f9869d0ee Use "alternative" instead of "alternate" where it is clearer. 2007-11-07 12:24:24 +00:00
18e3fcc31e Migrate the former contrib/txid module into core. This will make it easier
for Slony and Skytools to depend on it.  Per discussion.
2007-10-13 23:06:28 +00:00
537e92e41f Fix ALTER COLUMN TYPE to preserve the tablespace and reloptions of indexes
it affects.  The original coding neglected tablespace entirely (causing
the indexes to move to the database's default tablespace) and for an index
belonging to a UNIQUE or PRIMARY KEY constraint, it would actually try to
assign the parent table's reloptions to the index :-(.  Per bug #3672 and
subsequent investigation.

8.0 and 8.1 did not have reloptions, but the tablespace bug is present.
2007-10-13 15:55:40 +00:00
f828f878e9 Change on-disk representation of NUMERIC datatype so that the sign_dscale
word comes before the weight instead of after.  This will allow future
binary-compatible extension of the representation to support compact formats,
as discussed on pgsql-hackers around 2007/06/18.  The reason to do it now is
that we've already pretty well broken any chance of simple in-place upgrade
from 8.2 to 8.3, but it's possible that 8.3 to 8.4 (or whenever we get around
to squeezing NUMERIC) could otherwise be data-compatible.
2007-09-25 22:21:55 +00:00
02138357ff Remove "convert 'blah' using conversion_name" facility, because if it
produces text it is an encoding hole and if not it's incompatible
with the spec, whatever the spec means (which we're not sure about anyway).
2007-09-24 01:29:30 +00:00
282d2a03dd HOT updates. When we update a tuple without changing any of its indexed
columns, and the new version can be stored on the same heap page, we no longer
generate extra index entries for the new version.  Instead, index searches
follow the HOT-chain links to ensure they find the correct tuple version.

In addition, this patch introduces the ability to "prune" dead tuples on a
per-page basis, without having to do a complete VACUUM pass to recover space.
VACUUM is still needed to clean up dead index entries, however.

Pavan Deolasee, with help from a bunch of other people.
2007-09-20 17:56:33 +00:00
55613bf9cd Close previously open holes for invalidly encoded data to enter the
database via builtin functions, as recently discussed on -hackers.

chr() now returns a character in the database encoding. For UTF8 encoded databases
the argument is treated as a Unicode code point. For other multi-byte encodings
the argument must designate a strict ascii character, or an error is raised,
as is also the case if the argument is 0.

ascii() is adjusted so that it remains the inverse of chr().

The two argument form of convert() is gone, and the three argument form now
takes a bytea first argument and returns a bytea. To cover this loss three new
functions are introduced:
. convert_from(bytea, name) returns text - converts the first argument from the
  named encoding to the database encoding
. convert_to(text, name) returns bytea - converts the first argument from the
  database encoding to the named encoding
. length(bytea, name) returns int - gives the length of the first argument in
  characters in the named encoding
2007-09-18 17:41:17 +00:00
82a47982f3 Arrange for SET LOCAL's effects to persist until the end of the current top
transaction, unless rolled back or overridden by a SET clause for the same
variable attached to a surrounding function call.  Per discussion, these
seem the best semantics.  Note that this is an INCOMPATIBLE CHANGE: in 8.0
through 8.2, SET LOCAL's effects disappeared at subtransaction commit
(leading to behavior that made little sense at the SQL level).

I took advantage of the opportunity to rewrite and simplify the GUC variable
save/restore logic a little bit.  The old idea of a "tentative" value is gone;
it was a hangover from before we had a stack.  Also, we no longer need a stack
entry for every nesting level, but only for those in which a variable's value
actually changed.
2007-09-11 00:06:42 +00:00
40fda15dce Code review for GUC revert-values-if-removed-from-postgresql.conf patch;
and in passing, fix some bogosities dating from the custom_variable_classes
patch.  Fix guc-file.l to correctly check changes in custom_variable_classes
that are attempted concurrently with additions/removals of custom variables,
and don't allow the new setting to be applied in advance of checking it.
Clean up messy and undocumented situation for string variables with NULL
boot_val.  Fix DefineCustomVariable functions to initialize boot_val
correctly.  Prevent find_option from inserting bogus placeholders for custom
variables that are simply inquired about rather than being set.
2007-09-10 00:57:22 +00:00
2e74c53ec1 Provide for binary input/output of enums, to fix complaint from Merlin Moncure.
This just provides text values, we're not exposing the underlying Oid representation.
Catalog version bumped.
2007-09-04 16:41:43 +00:00
e7889b83b7 Support SET FROM CURRENT in CREATE/ALTER FUNCTION, ALTER DATABASE, ALTER ROLE.
(Actually, it works as a plain statement too, but I didn't document that
because it seems a bit useless.)  Unify VariableResetStmt with
VariableSetStmt, and clean up some ancient cruft in the representation of
same.
2007-09-03 18:46:30 +00:00
2abae34a2e Implement function-local GUC parameter settings, as per recent discussion.
There are still some loose ends: I didn't do anything about the SET FROM
CURRENT idea yet, and it's not real clear whether we are happy with the
interaction of SET LOCAL with function-local settings.  The documentation
is a bit spartan, too.
2007-09-03 00:39:26 +00:00
0ee5a39862 Apply a band-aid fix for the problem that 8.2 and up completely misestimate
the number of rows likely to be produced by a query such as
	SELECT * FROM t1 LEFT JOIN t2 USING (key) WHERE t2.key IS NULL;
What this is doing is selecting for t1 rows with no match in t2, and thus
it may produce a significant number of rows even if the t2.key table column
contains no nulls at all.  8.2 thinks the table column's null fraction is
relevant and thus may estimate no rows out, which results in terrible plans
if there are more joins above this one.  A proper fix for this will involve
passing much more information about the context of a clause to the selectivity
estimator functions than we ever have.  There's no time left to write such a
patch for 8.3, and it wouldn't be back-patchable into 8.2 anyway.  Instead,
put in an ad-hoc test to defeat the normal table-stats-based estimation when
an IS NULL test is evaluated at an outer join, and just use a constant
estimate instead --- I went with 0.5 for lack of a better idea.  This won't
catch every case but it will catch the typical ways of writing such queries,
and it seems unlikely to make things worse for other queries.
2007-08-31 23:35:22 +00:00
6c96188cb5 Remove the 'not in' operator (!!=). This was a hangover from Berkeley
days that was obsolete the moment we had IN (SELECT ...) capability.
It's arguably a security hole since it applied no permissions check to
the table it searched, and since it was never documented anywhere,
removing it seems more appropriate than fixing it.
2007-08-27 01:39:25 +00:00
140d4ebcb4 Tsearch2 functionality migrates to core. The bulk of this work is by
Oleg Bartunov and Teodor Sigaev, but I did a lot of editorializing,
so anything that's broken is probably my fault.

Documentation is nonexistent as yet, but let's land the patch so we can
get some portability testing done.
2007-08-21 01:11:32 +00:00
fd801f4faa Provide for logfiles in machine readable CSV format. In consequence, rename
redirect_stderr to logging_collector.
Original patch from Arul Shaji, subsequently modified by Greg Smith, and then
heavily modified by me.
2007-08-19 01:41:25 +00:00
67f99d216a Fix oversight in async-commit patch: there were some places in heapam.c
that still thought they could set HEAP_XMAX_COMMITTED immediately after
seeing the other transaction commit.  Make them use the same logic as
tqual.c does to determine if the hint bit can be set yet.
2007-08-14 17:35:18 +00:00
8d30337566 Fix up bad layout of some comments (probably pg_indent's fault), and
improve grammar a tad.  Per Greg Stark.
2007-08-04 21:53:00 +00:00
906b2e1b37 Rename DLLIMPORT macro to PGDLLIMPORT to avoid conflict with
third party includes (like tcl) that define DLLIMPORT.
2007-07-25 12:22:54 +00:00
474774918b Implement CREATE TABLE LIKE ... INCLUDING INDEXES. Patch from NikhilS,
based in part on an earlier patch from Trevor Hardcastle, and reviewed
by myself.
2007-07-17 05:02:03 +00:00
7af3a6fc6f Fix up hash functions for datetime datatypes so that they don't take
unwarranted liberties with int8 vs float8 values for these types.
Specifically, be sure to apply either hashint8 or hashfloat8 depending
on HAVE_INT64_TIMESTAMP.  Per my gripe of even date.
2007-07-06 04:16:00 +00:00
80f3b5ad2e Remove unused "caller" argument from stringToQualifiedNameList. 2007-06-26 16:48:09 +00:00
23347231a5 Tweak the API for per-datatype typmodin functions so that they are passed
an array of strings rather than an array of integers, and allow any simple
constant or identifier to be used in typmods; for example
	create table foo (f1 widget(42,'23skidoo',point));
Of course the typmodin function has still got to pack this info into a
non-negative int32 for storage, but it's still a useful improvement in
flexibility, especially considering that you can do nearly anything if you
are willing to keep the info in a side table.  We can get away with this
change since we have not yet released a version providing user-definable
typmods.  Per discussion.
2007-06-15 20:56:52 +00:00
8be9b50ab4 Minor comment fixes. 2007-06-12 16:01:31 +00:00
2d4db3675f Fix up text concatenation so that it accepts all the reasonable cases that
were accepted by prior Postgres releases.  This takes care of the loose end
left by the preceding patch to downgrade implicit casts-to-text.  To avoid
breaking desirable behavior for array concatenation, introduce a new
polymorphic pseudo-type "anynonarray" --- the added concatenation operators
are actually text || anynonarray and anynonarray || text.
2007-06-06 23:00:50 +00:00
31edbadf4a Downgrade implicit casts to text to be assignment-only, except for the ones
from the other string-category types; this eliminates a lot of surprising
interpretations that the parser could formerly make when there was no directly
applicable operator.

Create a general mechanism that supports casts to and from the standard string
types (text,varchar,bpchar) for *every* datatype, by invoking the datatype's
I/O functions.  These new casts are assignment-only in the to-string direction,
explicit-only in the other, and therefore should create no surprising behavior.
Remove a bunch of thereby-obsoleted datatype-specific casting functions.

The "general mechanism" is a new expression node type CoerceViaIO that can
actually convert between *any* two datatypes if their external text
representations are compatible.  This is more general than needed for the
immediate feature, but might be useful in plpgsql or other places in future.

This commit does nothing about the issue that applying the concatenation
operator || to non-text types will now fail, often with strange error messages
due to misinterpreting the operator as array concatenation.  Since it often
(not always) worked before, we should either make it succeed or at least give
a more user-friendly error; but details are still under debate.

Peter Eisentraut and Tom Lane
2007-06-05 21:31:09 +00:00
1120b99445 The session_replication_role actually can be changed at will during
a session regardless of the existence of cached plans. The plancache
only needs to be invalidated so that rules affected by the new setting
will be reflected in the new query plans.

Jan
2007-06-05 20:00:41 +00:00
acfce502ba Create a GUC parameter temp_tablespaces that allows selection of the
tablespace(s) in which to store temp tables and temporary files.  This is a
list to allow spreading the load across multiple tablespaces (a random list
element is chosen each time a temp object is to be created).  Temp files are
not stored in per-database pgsql_tmp/ directories anymore, but per-tablespace
directories.

Jaime Casanova and Albert Cervera, with review by Bernd Helmle and Tom Lane.
2007-06-03 17:08:34 +00:00
f086be3d39 Allow leading and trailing whitespace in the input to the boolean
type. Also, add explicit casts between boolean and text/varchar. Both
of these changes are for conformance with SQL:2003.

Update the regression tests, bump the catversion.
2007-06-01 23:40:19 +00:00
6af04882de Fix a bug in input processing for the "interval" type. Previously,
"microsecond" and "millisecond" units were not considered valid input
by themselves, which caused inputs like "1 millisecond" to be rejected
erroneously.

Update the docs, add regression tests, and backport to 8.2 and 8.1
2007-05-29 04:58:43 +00:00
77947c51c0 Fix up pgstats counting of live and dead tuples to recognize that committed
and aborted transactions have different effects; also teach it not to assume
that prepared transactions are always committed.

Along the way, simplify the pgstats API by tying counting directly to
Relations; I cannot detect any redeeming social value in having stats
pointers in HeapScanDesc and IndexScanDesc structures.  And fix a few
corner cases in which counts might be missed because the relation's
pgstat_info pointer hadn't been set.
2007-05-27 03:50:39 +00:00
2415ad9831 Teach tuplestore.c to throw away data before the "mark" point when the caller
is using mark/restore but not rewind or backward-scan capability.  Insert a
materialize plan node between a mergejoin and its inner child if the inner
child is a sort that is expected to spill to disk.  The materialize shields
the sort from the need to do mark/restore and thereby allows it to perform
its final merge pass on-the-fly; while the materialize itself is normally
cheap since it won't spill to disk unless the number of tuples with equal
key values exceeds work_mem.

Greg Stark, with some kibitzing from Tom Lane.
2007-05-21 17:57:35 +00:00
3963574d13 XPath fixes:
- Function renamed to "xpath".
 - Function is now strict, per discussion.
 - Return empty array in case when XPath expression detects nothing
   (previously, NULL was returned in such case), per discussion.
 - (bugfix) Work with fragments with prologue: select xpath('/a',
   '<?xml version="1.0"?><a /><b />'); // now XML datum is always wrapped
   with dummy <x>...</x>, XML prologue simply goes away (if any).
 - Some cleanup.

Nikolay Samokhvalov

Some code cleanup and documentation work by myself.
2007-05-21 17:10:29 +00:00
dbb769352d Temporary fix for the problem that pg_stat_activity, inet_client_addr(),
and inet_server_addr() fail if the client connected over a "scoped" IPv6
address.  In this case getnameinfo() will return a string ending with
a poorly-standardized "%something" zone specifier, which these functions
try to feed to network_in(), which won't take it.  So that we don't lose
functionality altogether, suppress the zone specifier before giving the
string to network_in().  Per report from Brian Hirt.

TODO: probably someday the inet type should support scoped IPv6 addresses,
and then this patch should be reverted.

Backpatch to 8.2 ... is it worth going further?
2007-05-17 23:31:49 +00:00
ade493e02d Add a hash function for "numeric". Mark the equality operator for
numerics as "oprcanhash", and make the corresponding system catalog
updates. As a result, hash indexes, hashed aggregation, and hash
joins can now be used with the numeric type. Bump the catversion.

The only tricky aspect to doing this is writing a correct hash
function: it's possible for two Numerics to be equal according to
their equality operator, but have different in-memory bit patterns.
To cope with this, the hash function doesn't consider the Numeric's
"scale" or "sign", and explictly skips any leading or trailing
zeros in the Numeric's digit buffer (the current implementation
should suppress any such zeros, but it seems unwise to rely upon
this). See discussion on pgsql-patches for more details.
2007-05-08 18:56:48 +00:00
d2a4a4069f Add a line to the EXPLAIN ANALYZE output for a Sort node, showing the
actual sort strategy and amount of space used.  By popular demand.
2007-05-04 21:29:53 +00:00
79ca7ffeb6 A few fixups in error handling: mark pg_re_throw() as noreturn for gcc,
and for other compilers, insert a dummy exit() call so that they understand
PG_RE_THROW() doesn't return.  Insert fflush(stderr) in ExceptionalCondition,
per recent buildfarm evidence that that might not happen automatically on some
platforms.  And const-ify ExceptionalCondition's declaration while at it.
2007-05-04 02:01:02 +00:00
d26559dbf3 Teach tuplesort.c about "top N" sorting, in which only the first N tuples
need be returned.  We keep a heap of the current best N tuples and sift-up
new tuples into it as we scan the input.  For M input tuples this means
only about M*log(N) comparisons instead of M*log(M), not to mention a lot
less workspace when N is small --- avoiding spill-to-disk for large M
is actually the most attractive thing about it.  Patch includes planner
and executor support for invoking this facility in ORDER BY ... LIMIT
queries.  Greg Stark, with some editorialization by moi.
2007-05-04 01:13:45 +00:00
88f1fd2989 Fix oversight in PG_RE_THROW processing: it's entirely possible that there
isn't any place to throw the error to.  If so, we should treat the error
as FATAL, just as we would have if it'd been thrown outside the PG_TRY
block to begin with.

Although this is clearly a *potential* source of bugs, it is not clear
at the moment whether it is an *actual* source of bugs; there may not
presently be any PG_TRY blocks in code that can be reached with no outer
longjmp catcher.  So for the moment I'm going to be conservative and not
back-patch this.  The change breaks ABI for users of PG_RE_THROW and hence
might create compatibility problems for loadable modules, so we should not
put it into released branches without proof that it's needed.
2007-05-02 15:32:42 +00:00
c432061963 Change the timestamps recorded in transaction commit/abort xlog records
from time_t to TimestampTz representation.  This provides full gettimeofday()
resolution of the timestamps, which might be useful when attempting to
do point-in-time recovery --- previously it was not possible to specify
the stop point with sub-second resolution.  But mostly this is to get
rid of TimestampTz-to-time_t conversion overhead during commit.  Per my
proposal of a day or two back.
2007-04-30 21:01:53 +00:00
957d08c81f Implement rate-limiting logic on how often backends will attempt to send
messages to the stats collector.  This avoids the problem that enabling
stats_row_level for autovacuum has a significant overhead for short
read-only transactions, as noted by Arjen van der Meijden.  We can avoid
an extra gettimeofday call by piggybacking on the one done for WAL-logging
xact commit or abort (although that doesn't help read-only transactions,
since they don't WAL-log anything).

In my proposal for this, I noted that we could change the WAL log entries
for commit/abort to record full TimestampTz precision, instead of only
time_t as at present.  That's not done in this patch, but will be committed
separately.
2007-04-30 03:23:49 +00:00
a2e923a652 Fix dynahash.c to suppress hash bucket splits while a hash_seq_search() scan
is in progress on the same hashtable.  This seems the least invasive way to
fix the recently-recognized problem that a split could cause the scan to
visit entries twice or (with much lower probability) miss them entirely.
The only field-reported problem caused by this is the "failed to re-find
shared lock object" PANIC in COMMIT PREPARED reported by Michel Dorochevsky,
which was caused by multiply visited entries.  However, it seems certain
that mdsync() is vulnerable to missing required fsync's due to missed
entries, and I am fearful that RelationCacheInitializePhase2() might be at
risk as well.  Because of that and the generalized hazard presented by this
bug, back-patch all the supported branches.

Along the way, fix pg_prepared_statement() and pg_cursor() to not assume
that the hashtables they are examining will stay static between calls.
This is risky regardless of the newly noted dynahash problem, because
hash_seq_search() has never promised to cope with deletion of table entries
other than the just-returned one.  There may be no bug here because the only
supported way to call these functions is via ExecMakeTableFunctionResult()
which will cycle them to completion before doing anything very interesting,
but it seems best to get rid of the assumption.  This affects 8.2 and HEAD
only, since those functions weren't there earlier.
2007-04-26 23:24:46 +00:00
b7edb568bd Make configuration parameters fall back to their default values when they
are removed from the configuration file.

Joachim Wieland
2007-04-21 20:02:41 +00:00
42dc4b66e6 Make plancache store cursor options so it can pass them to planner during
a replan.  I had originally thought this was not necessary, but the new
SPI facilities create a path whereby queries planned with non-default
options can get into the cache, so it is necessary.
2007-04-16 18:21:07 +00:00
d13e903bea RESET SESSION, plus related new DDL commands. Patch from Marko Kreen,
reviewed by Neil Conway. This patch adds the following DDL command
variants: RESET SESSION, RESET TEMP, RESET PLANS, CLOSE ALL, and
DEALLOCATE ALL. RESET SESSION is intended for use by connection
pool software and the like, in order to reset a client session
to something close to its initial state.

Note that while most of these command variants can be executed
inside a transaction block (but are not transaction-aware!),
RESET SESSION cannot. While this is inconsistent, it is intended
to catch programmer mistakes: RESET SESSION in an open transaction
block is probably unintended.
2007-04-12 06:53:49 +00:00
3e23b68dac Support varlena fields with single-byte headers and unaligned storage.
This commit breaks any code that assumes that the mere act of forming a tuple
(without writing it to disk) does not "toast" any fields.  While all available
regression tests pass, I'm not totally sure that we've fixed every nook and
cranny, especially in contrib.

Greg Stark with some help from Tom Lane
2007-04-06 04:21:44 +00:00
57690c6803 Support enum data types. Along the way, use macros for the values of
pg_type.typtype whereever practical.  Tom Dunstan, with some kibitzing
from Tom Lane.
2007-04-02 03:49:42 +00:00
0b75afda92 Mapping schemas and databases to XML and XML Schema.
Refactor and document the remaining mapping code.
2007-04-01 09:00:26 +00:00
fba8113c1b Teach CLUSTER to skip writing WAL if not needed (ie, not using archiving)
--- Simon.
Also, code review and cleanup for the previous COPY-no-WAL patches --- Tom.
2007-03-29 00:15:39 +00:00