and regexp_split_to_table. These functions provide access to the
capture groups resulting from a POSIX regular expression match,
and provide the ability to split a string on a POSIX regular
expression, respectively. Patch from Jeremy Drake; code review by
Neil Conway, additional comments and suggestions from Tom and
Peter E.
This patch bumps the catversion, adds some regression tests,
and updates the docs.
BTW, the comment in this file says that we hope we never have more than
10 catversion changes per day, but to even make this possible we should
start counting at zero, shouldn't we?
Jan
rules to be defined with different, per session controllable, behaviors
for replication purposes.
This will allow replication systems like Slony-I and, as has been stated
on pgsql-hackers, other products to control the firing mechanism of
triggers and rewrite rules without modifying the system catalog directly.
The firing mechanisms are controlled by a new superuser-only GUC
variable, session_replication_role, together with a change to
pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both
columns are a single char data type now (tgenabled was a bool before).
The possible values in these attributes are:
'O' - Trigger/Rule fires when session_replication_role is "origin"
(default) or "local". This is the default behavior.
'D' - Trigger/Rule is disabled and fires never
'A' - Trigger/Rule fires always regardless of the setting of
session_replication_role
'R' - Trigger/Rule fires when session_replication_role is "replica"
The GUC variable can only be changed as long as the system does not have
any cached query plans. This will prevent changing the session role and
accidentally executing stored procedures or functions that have plans
cached that expand to the wrong query set due to differences in the rule
firing semantics.
The SQL syntax for changing a triggers/rules firing semantics is
ALTER TABLE <tabname> <when> TRIGGER|RULE <name>;
<when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE
psql's \d command as well as pg_dump are extended in a backward
compatible fashion.
Jan
available information about the typmod of an expression; namely, Const,
ArrayRef, ArrayExpr, and EXPR and ARRAY SubLinks. In the ArrayExpr and
SubLink cases it wasn't really the data structure's fault, but exprTypmod()
being lazy. This seems like a good idea in view of the expected increase in
typmod usage from Teodor's work to allow user-defined types to have typmods.
In particular this responds to the concerns we had about eliminating the
special-purpose hack that exprTypmod() used to have for BPCHAR Consts.
We can now tell whether or not such a Const has been cast to a specific
length, and report or display properly if so.
initdb forced due to changes in stored rules.
this, add a 16-bit "flags" field to page headers by stealing some bits from
pd_tli. We use one flag bit as a hint to indicate whether there are any
unused line pointers; the remaining 15 are available for future use.
This is a cut-down form of an idea proposed by Hiroki Kataoka in July 2005.
At the time it was rejected because the original patch increased the size of
page headers and it wasn't clear that the benefit outweighed the distributed
cost. The flag-bit approach gets most of the benefit without requiring an
increase in the page header size.
Heikki Linnakangas and Tom Lane
storing mostly-redundant Query trees in prepared statements, portals, etc.
To replace Query, a new node type called PlannedStmt is inserted by the
planner at the top of a completed plan tree; this carries just the fields of
Query that are still needed at runtime. The statement lists kept in portals
etc. now consist of intermixed PlannedStmt and bare utility-statement nodes
--- no Query. This incidentally allows us to remove some fields from Query
and Plan nodes that shouldn't have been there in the first place.
Still to do: simplify the execution-time range table; at the moment the
range table passed to the executor still contains Query trees for subqueries.
initdb forced due to change of stored rules.
equality checks it applies, instead of a random dependence on whatever
operators might be named "=". The equality operators will now be selected
from the opfamily of the unique index that the FK constraint depends on to
enforce uniqueness of the referenced columns; therefore they are certain to be
consistent with that index's notion of equality. Among other things this
should fix the problem noted awhile back that pg_dump may fail for foreign-key
constraints on user-defined types when the required operators aren't in the
search path. This also means that the former warning condition about "foreign
key constraint will require costly sequential scans" is gone: if the
comparison condition isn't indexable then we'll reject the constraint
entirely. All per past discussions.
Along the way, make the RI triggers look into pg_constraint for their
information, instead of using pg_trigger.tgargs; and get rid of the always
error-prone fixed-size string buffers in ri_triggers.c in favor of building up
the RI queries in StringInfo buffers.
initdb forced due to columns added to pg_constraint and pg_trigger.
keeping private state in each backend that has inserted and deleted the same
tuple during its current top-level transaction. This is sufficient since
there is no need to be able to determine the cmin/cmax from any other
transaction. This gets us back down to 23-byte headers, removing a penalty
paid in 8.0 to support subtransactions. Patch by Heikki Linnakangas, with
minor revisions by moi, following a design hashed out awhile back on the
pghackers list.
already collected in the current transaction; this allows plpgsql functions to
watch for stats updates even though they are confined to a single transaction.
Use this instead of the previous kluge involving pg_stat_file() to wait for
the stats collector to update in the stats regression test. Internally,
decouple storage of stats snapshots from transaction boundaries; they'll
now stick around until someone calls pgstat_clear_snapshot --- which xact.c
still does at transaction end, to maintain the previous behavior. This makes
the logic a lot cleaner, at the price of a couple dozen cycles per transaction
exit.
that aren't turned into true joins). Since this is the last missing bit of
infrastructure, go ahead and fill out the hash integer_ops and float_ops
opfamilies with cross-type operators. The operator family project is now
DONE ... er, except for documentation ...
describe the maximum size of index tuples (which is typically AM-dependent
anyway); and consequently remove the bogus deduction for "special space"
that was built into it.
Adjust TOAST_TUPLE_THRESHOLD and TOAST_MAX_CHUNK_SIZE to avoid wasting two
bytes per toast chunk, and to ensure that the calculation correctly tracks any
future changes in page header size. The computation had been inaccurate in a
way that didn't cause any harm except space wastage, but future changes could
have broken it more drastically.
Fix the calculation of BTMaxItemSize, which was formerly computed as 1 byte
more than it could safely be. This didn't cause any harm in practice because
it's only compared against maxalign'd lengths, but future changes in the size
of page headers or btree special space could have exposed the problem.
initdb forced because of change in TOAST_MAX_CHUNK_SIZE, which alters the
storage of toast tables.
observe the xmloption.
Reorganize the representation of the XML option in the parse tree and the
API to make it easier to manage and understand.
Add regression tests for parsing back XML expressions.
nonportable "hh" sprintf(3) length modifier. Instead, do the parsing
and output by hand. The code to do this isn't ideal, but this is
an interim measure anyway: the uuid type should probably use the
in-memory struct layout specified by RFC 4122. For now, this patch
should hopefully rectify the buildfarm failures for the uuid test.
Along the way, re-add pg_cast entries for uuid <-> varchar, which
I mistakenly removed earlier, and bump the catversion.
that defined in RFC 4122. This patch includes the basic implementation,
plus regression tests. Documentation and perhaps some additional
functionality will come later. Catversion bumped.
Patch from Gevik Babakhani; review from Peter, Tom, and myself.
columns procost and prorows, to allow simple user adjustment of the estimated
cost of a function call, as well as control of the estimated number of rows
returned by a set-returning function. We might eventually wish to extend this
to allow function-specific estimation routines, but there seems to be
consensus that we should try a simple constant estimate first. In particular
this provides a relatively simple way to control the order in which different
WHERE clauses are applied in a plan node, which is a Good Thing in view of the
fact that the recent EquivalenceClass planner rewrite made that much less
predictable than before.
provide just a boolean 'amcanorder', instead of fields that specify the
sort operator strategy numbers. We have decided to require ordering-capable
AMs to use btree-compatible strategy numbers, so the old fields are
overkill (and indeed misleading about what's allowed).
The implementation is somewhat ugly logic-wise, but I don't see an
easy way to make it more concise.
When writing this, I noticed that my previous implementation of
width_bucket() doesn't handle NaN correctly:
postgres=# select width_bucket('NaN', 1, 5, 5);
width_bucket
--------------
6
(1 row)
AFAICS SQL:2003 does not define a NaN value, so it doesn't address how
width_bucket() should behave here. The patch changes width_bucket() so
that ereport(ERROR) is raised if NaN is specified for the operand or the
lower or upper bounds to width_bucket(). For float8, NaN is disallowed
for any of the floating-point inputs, and +/- infinity is disallowed
for the histogram bounds (but allowed for the operand).
Update docs and regression tests, bump the catversion.
per-column options for btree indexes. The planner's support for this is still
pretty rudimentary; it does not yet know how to plan mergejoins with
nondefault ordering options. The documentation is pretty rudimentary, too.
I'll work on improving that stuff later.
Note incompatible change from prior behavior: ORDER BY ... USING will now be
rejected if the operator is not a less-than or greater-than member of some
btree opclass. This prevents less-than-sane behavior if an operator that
doesn't actually define a proper sort ordering is selected.
The purpose is to allow autovacuum-esq conditional vacuuming and
clustering using SQL to discover the required stats.
No documentation updates required. Catalog version updated.
Glen Parker
the 8.1 SQL function definition for it. Per report from Rajesh Kumar Mallah,
such a DBA error doesn't seem at all improbable, and the cost of checking for
it is not very high compared to the cost of running this function. (It would
have been better to change the C name of the function so it wouldn't be called
by the old SQL definition, but it's too late for that now in the 8.2 branch.)
the XmlExpr code in various lists, use a representation that has some hope
of reverse-listing correctly (though it's still a de-escaping function
shy of correctness), generally try to make it look more like Postgres
coding conventions.
cases. Operator classes now exist within "operator families". While most
families are equivalent to a single class, related classes can be grouped
into one family to represent the fact that they are semantically compatible.
Cross-type operators are now naturally adjunct parts of a family, without
having to wedge them into a particular opclass as we had done originally.
This commit restructures the catalogs and cleans up enough of the fallout so
that everything still works at least as well as before, but most of the work
needed to actually improve the planner's behavior will come later. Also,
there are not yet CREATE/DROP/ALTER OPERATOR FAMILY commands; the only way
to create a new family right now is to allow CREATE OPERATOR CLASS to make
one by default. I owe some more documentation work, too. But that can all
be done in smaller pieces once this infrastructure is in place.
operator strategy numbers, ie, GiST and GIN. This is almost cosmetic
enough to not need a catversion bump, but since the opr_sanity regression
test has to change in sync with the catalog entry, I figured I'd better
do one.
representing externally-supplied values, since the APIs that carry such
values only specify type not typmod. However, for PARAM_SUBLINK Params
it is handy to carry the typmod of the sublink's output column. This
is a much cleaner solution for the recently reported 'could not find
pathkey item to sort' and 'failed to find unique expression in subplan
tlist' bugs than my original 8.2-compatible patch. Besides, someday we
might want to support typmods for external parameters ...
in normal operation, and we can avoid rewriting pg_control at every log
segment switch if we don't insist that these values be valid. Reducing
the number of pg_control updates is a good idea for both performance and
reliability. It does make pg_resetxlog's life a bit harder, but that seems
a good tradeoff; and anyway the change to pg_resetxlog amounts to automating
something people formerly needed to do by hand, namely look at the existing
pg_xlog files to make sure the new WAL start point was past them.
In passing, change the wording of xlog.c's "database system was interrupted"
messages: describe the pg_control timestamp as "last known up at" rather than
implying it is the exact time of service interruption. With this change the
timestamp will generally be the time of the last checkpoint, which could be
many minutes before the failure; and we've already seen indications that
people tend to misinterpret the old wording.
initdb forced due to change in pg_control layout. Simon Riggs and Tom Lane
identify long-running transactions. Since we already need to record
the transaction-start time (e.g. for now()), we don't need any
additional system calls to report this information.
Catversion bumped, initdb required.
result now depends on the lc_messages setting, as noted by Bruce.
Also, mark to_number() and the numeric-type variants of to_char() as stable,
because their results depend on lc_numeric; this is a longstanding oversight.
Also, mark to_date() and to_char(interval) as stable; although these appear
not to depend on any GUC variables as of CVS HEAD, that seems a property
unlikely to survive future improvements. It seems best to mark all the
formatting functions stable and be done with it.
catversion not bumped, because this does not seem critical enough to force
a post-RC1 initdb, and anyway we cannot do so in the back branches.
vacuum/analyze timestamp columns at the end, rather than at a random
spot in the middle as in the original patch. This was deemed more usable
as well as less likely to break existing application code. initdb forced
accordingly. In passing, remove former kluge for initializing
pg_stat_file()'s pg_proc entry --- bootstrap mode was fixed recently
so that this can be done without any hacks, but I overlooked this usage.
in PITR scenarios. We now WAL-log the replacement of old XIDs with
FrozenTransactionId, so that such replacement is guaranteed to propagate to
PITR slave databases. Also, rather than relying on hint-bit updates to be
preserved, pg_clog is not truncated until all instances of an XID are known to
have been replaced by FrozenTransactionId. Add new GUC variables and
pg_autovacuum columns to allow management of the freezing policy, so that
users can trade off the size of pg_clog against the amount of freezing work
done. Revise the already-existing code that forces autovacuum of tables
approaching the wraparound point to make it more bulletproof; also, revise the
autovacuum logic so that anti-wraparound vacuuming is done per-table rather
than per-database. initdb forced because of changes in pg_class, pg_database,
and pg_autovacuum catalogs. Heikki Linnakangas, Simon Riggs, and Tom Lane.
contrib functionality. Along the way, remove the USER_LOCKS configuration
symbol, since it no longer makes any sense to try to compile that out.
No user documentation yet ... mmoncure has promised to write some.
Thanks to Abhijit Menon-Sen for creating a first draft to work from.
and create a new view pg_timezone_names that provides information about
the zones known in the 'zic' database. Magnus Hagander, with some
additional work by Tom Lane.
a schema is our own temp schema or another backend's temp schema, and use
these in place of some former kluges in information_schema. Per my
proposal of yesterday.
agreed these symbols are less easily confused. I made new pg_operator
entries (with new OIDs) for the old names, so as to provide backward
compatibility while making it pretty easy to remove the old names in
some future release cycle. This commit only touches the core datatypes,
contrib will be fixed separately.
