recursion when we are unable to convert a localized error message to the
client's encoding. We've been over this ground before, but as reported by
Ibrar Ahmed, it still didn't work in the case of conversion failures for
the conversion-failure message itself :-(. Fix by installing a "circuit
breaker" that disables attempts to localize this message once we get into
recursion trouble.
Patch all supported branches, because it is in fact broken in all of them;
though I had to add some missing translations to the older branches in
order to expose the failure in the particular test case I was using.
recent proposal. In typical cases, we now need 12 bytes per insert or delete
event and 16 bytes per update event; previously we needed 40 bytes per
event on 32-bit hardware and 80 bytes per event on 64-bit hardware. Even
in the worst case usage pattern with a large number of distinct triggers being
fired in one query, usage is at most 32 bytes per event. It seems to be a
bit faster than the old code as well, due to reduction of palloc overhead.
This commit doesn't address the TODO item of allowing the event list to spill
to disk; rather it's trying to stave off the need for that. However, it
probably makes that task a bit easier by reducing the data structure's
dependency on pointers. It would now be practical to dump an event list to
disk by "chunks" instead of individual events.
* make LDAP use this instead of the hacky previous method to specify
the DN to bind as
* make all auth options behave the same when they are not compiled
into the server
* rename "ident maps" to "user name maps", and support them for all
auth methods that provide an external username
This makes a backwards incompatible change in the format of pg_hba.conf
for the ident, PAM and LDAP authentication methods.
until vars are distributed to rels during query_planner() startup. We don't
really need it before that, and not building it early has some advantages.
First, we don't need to put it through the various preprocessing steps, which
saves some cycles and eliminates the need for a number of routines to support
PlaceHolderInfo nodes at all. Second, this means one less unused plan for any
sub-SELECT appearing in a placeholder's expression, since we don't build
placeholder_list until after sublink expansion is complete.
correctly set. As result, killtuple() marks as dead
wrong tuple on page. Bug was introduced by me while fixing
possible duplicates during GiST index scan.
that represent some expression that we desire to compute below the top level
of the plan, and then let that value "bubble up" as though it were a plain
Var (ie, a column value).
The immediate application is to allow sub-selects to be flattened even when
they are below an outer join and have non-nullable output expressions.
Formerly we couldn't flatten because such an expression wouldn't properly
go to NULL when evaluated above the outer join. Now, we wrap it in a
PlaceHolderVar and arrange for the actual evaluation to occur below the outer
join. When the resulting Var bubbles up through the join, it will be set to
NULL if necessary, yielding the correct results. This fixes a planner
limitation that's existed since 7.1.
In future we might want to use this mechanism to re-introduce some form of
Hellerstein's "expensive functions" optimization, ie place the evaluation of
an expensive function at the most suitable point in the plan tree.
This patch eliminates the marking of subtransactions as SUBCOMMITTED in pg_clog
during their commit; instead they remain in-progress until main transaction
commit. At main transaction commit, the commit protocol is atomic-by-page
instead of one transaction at a time. To avoid a race condition with some
subtransactions appearing committed before others in the case where they span
more than one pg_clog page, we conserve the logic that marks them subcommitted
before marking the parent committed.
Simon Riggs with minor help from me
scanning; GiST and GIN do not, and it seems like too much trouble to make
them do so. By teaching ExecSupportsBackwardScan() about this restriction,
we ensure that the planner will protect a scroll cursor from the problem
by adding a Materialize node.
In passing, fix another longstanding bug in the same area: backwards scan of
a plan with set-returning functions in the targetlist did not work either,
since the TupFromTlist expansion code pays no attention to direction (and
has no way to run a SRF backwards anyway). Again the fix is to make
ExecSupportsBackwardScan check this restriction.
Also adjust the index AM API specification to note that mark/restore support
is unnecessary if the AM can't produce ordered output.
is NULL but SK_SEARCHNULL is not set. Add checking IS NULL of keys
to set during key initialization. If key is NULL and SK_SEARCHNULL is not
set then nothnig can be satisfied.
With assert-enabled compilation that causes coredump.
Bug was introduced in 8.3 by support of IS NULL index scan.
the timestamp types. Turns out this doesn't even reduce the available
range of dates, since the restriction to dates that work for Julian-date
arithmetic is much tighter than the int32 range anyway. Per a longstanding
TODO item.
pseudo-type record[] to represent arrays of possibly-anonymous composite
types. Since composite datums carry their own type identification, no
extra knowledge is needed at the array level.
The main reason for doing this right now is that it is necessary to support
the general case of detection of cycles in recursive queries: if you need to
compare more than one column to detect a cycle, you need to compare a ROW()
to an array built from ROW()s, at least if you want to do it as the spec
suggests. Add some documentation and regression tests concerning the cycle
detection issue.
of referencing a WITH item that's not yet in scope according to the SQL
spec's semantics. This seems to be an easy error to make, and the bare
"relation doesn't exist" message doesn't lead one's mind in the correct
direction to fix it.
implementation uses an in-memory hash table, so it will poop out for very
large recursive results ... but the performance characteristics of a
sort-based implementation would be pretty unpleasant too.
get_name_for_var_field didn't have enough context to interpret a reference to
a CTE query's output. Fixing this requires separate hacks for the regular
deparse case (pg_get_ruledef) and for the EXPLAIN case, since the available
context information is quite different. It's pretty nearly parallel to the
existing code for SUBQUERY RTEs, though. Also, add code to make sure we
qualify a relation name that matches a CTE name; else the CTE will mistakenly
capture the reference when reloading the rule.
In passing, fix a pre-existing problem with get_name_for_var_field not working
on variables in targetlists of SubqueryScan plan nodes. Although latent all
along, this wasn't a problem until we made EXPLAIN VERBOSE try to print
targetlists. To do this, refactor the deparse_context_for_plan API so that
the special case for SubqueryScan is all on ruleutils.c's side.
the column alias names of the RTE referenced by the Var to the RowExpr.
This is needed to allow ruleutils.c to correctly deparse FieldSelect nodes
referencing such a construct. Per my recent bug report.
Adding a field to RowExpr forces initdb (because of stored rules changes)
so this solution is not back-patchable; which is unfortunate because 8.2
and 8.3 have this issue. But it only affects EXPLAIN for some pretty odd
corner cases, so we can probably live without a solution for the back
branches.
relation forks. While the file names are not visible to users, for those
that do peek into the data directory, it's nice to have more descriptive
names. Per Greg Stark's suggestion.
well as regular tables. Per discussion, this seems necessary to meet the
principle of least astonishment.
In passing, simplify the error messages in warnAutoRange(). Now that we
have parser error position info for these errors, it doesn't seem very
useful to word the error message differently depending on whether we are
inside a sub-select or not.
There are some unimplemented aspects: recursive queries must use UNION ALL
(should allow UNION too), and we don't have SEARCH or CYCLE clauses.
These might or might not get done for 8.4, but even without them it's a
pretty useful feature.
There are also a couple of small loose ends and definitional quibbles,
which I'll send a memo about to pgsql-hackers shortly. But let's land
the patch now so we can get on with other development.
Yoshiyuki Asaba, with lots of help from Tatsuo Ishii and Tom Lane
name of a fork ('main' or 'fsm', at the moment) to pg_relation_size() to
get the size of a specific fork. Defaults to 'main', if none given.
While we're at it, modify pg_relation_size to take a regclass as argument,
instead of separate variants taking oid and name. This change is
transparent to typical use where the table name is passed as a string
literal, like pg_relation_size('table'), but will break queries like
pg_relation_size(namecol), where namecol is of type name. text-type input
still works, and using a non-schema-qualified table name is not very
reliable anyway, so this is unlikely to break anyone's queries in practice.
This facility replaces the former mark/restore support but is otherwise
upward-compatible with previous uses. It's expected to be needed for
single evaluation of CTEs and also for window functions, so I'm committing
it separately instead of waiting for either one of those patches to be
finished. Per discussion with Greg Stark and Hitoshi Harada.
Note: I removed nodeFunctionscan's mark/restore support, instead of bothering
to update it for this change, because it was dead code anyway.
free space information is stored in a dedicated FSM relation fork, with each
relation (except for hash indexes; they don't use FSM).
This eliminates the max_fsm_relations and max_fsm_pages GUC options; remove any
trace of them from the backend, initdb, and documentation.
Rewrite contrib/pg_freespacemap to match the new FSM implementation. Also
introduce a new variant of the get_raw_page(regclass, int4, int4) function in
contrib/pageinspect that let's you to return pages from any relation fork, and
a new fsm_page_contents() function to inspect the new FSM pages.
element types. Since the backend doesn't actually pay attention to the array
type's delimiter, this has no functional effect, but it seems better for the
catalog entries to be consistent. Per gripe from Greg Mullane and subsequent
discussion.
ctype are now more like encoding, stored in new datcollate and datctype
columns in pg_database.
This is a stripped-down version of Radek Strnad's patch, with further
changes by me.
forestalls potential overflow when the same table (or other object, but
usually tables) is accessed by very many successive queries within a single
transaction. Per report from Michael Milligan.
Back-patch to 8.0, which is as far back as the patch conveniently applies.
There have been no reports of overflow in pre-8.3 releases, but clearly the
risk existed all along. (Michael's report suggests that 8.3 may consume lock
counts faster than prior releases, but with no test case to look at it's hard
to be sure about that. Widening the counts seems a good future-proofing
measure in any event.)
we regenerate the SQL query text not merely the plan derived from it. This
is needed to handle contingencies such as renaming of a table or column
used in an FK. Pre-8.3, such cases worked despite the lack of replanning
(because the cached plan needn't actually change), so this is a regression.
Per bug #4417 from Benjamin Bihler.
value. This means that hash index lookups are always lossy and have to be
rechecked when the heap is visited; however, the gain in index compactness
outweighs this when the indexed values are wide. Also, we only need to
perform datatype comparisons when the hash codes match exactly, rather than
for every entry in the hash bucket; so it could also win for datatypes that
have expensive comparison functions. A small additional win is gained by
keeping hash index pages sorted by hash code and using binary search to reduce
the number of index tuples we have to look at.
Xiao Meng
This commit also incorporates Zdenek Kotala's patch to isolate hash metapages
and hash bitmaps a bit better from the page header datastructures.
each connection. This makes it possible to catch errors in the pg_hba
file when it's being reloaded, instead of silently reloading a broken
file and failing only when a user tries to connect.
This patch also makes the "sameuser" argument to ident authentication
optional.
a lot closer than it was before). To do this, tweak coerce_type() to pass
through the typmod information when invoking interval_in() on an UNKNOWN
constant; then fix DecodeInterval to pay attention to the typmod when deciding
how to interpret a units-less integer value. I changed one or two other
details as well. I believe the code now reacts as expected by spec for all
the literal syntaxes that are specifically enumerated in the spec. There
are corner cases involving strings that don't exactly match the set of fields
called out by the typmod, for which we might want to tweak the behavior some
more; but I think this is an area of user friendliness rather than spec
compliance. There remain some non-compliant details about the SQL syntax
(as opposed to what's inside the literal string); but at least we'll throw
error rather than silently doing the wrong thing in those cases.
when user-defined functions used in a plan are modified. Also invalidate
plans when schemas, operators, or operator classes are modified; but for these
cases we just invalidate everything rather than tracking exact dependencies,
since these types of objects seldom change in a production database.
Tom Lane; loosely based on a patch by Martin Pihlak.
In support of that, create a backend function pg_get_functiondef().
The psql command is functional but maybe a bit rough around the edges...
Abhijit Menon-Sen
