pg_stat_statements now hashes selected fields of the analyzed parse tree
to assign a "fingerprint" to each query, and groups all queries with the
same fingerprint into a single entry in the pg_stat_statements view.
In practice it is expected that queries with the same fingerprint will be
equivalent except for values of literal constants. To make the display
more useful, such constants are replaced by "?" in the displayed query
strings.
This mechanism currently supports only optimizable queries (SELECT,
INSERT, UPDATE, DELETE). Utility commands are still matched on the
basis of their literal query strings.
There remain some open questions about how to deal with utility statements
that contain optimizable queries (such as EXPLAIN and SELECT INTO) and how
to deal with expiring speculative hashtable entries that are made to save
the normalized form of a query string. However, fixing these issues should
require only localized changes, and since there are other open patches
involving contrib/pg_stat_statements, it seems best to go ahead and commit
what we've got.
Peter Geoghegan, reviewed by Daniel Farina
Currently, the only way to see the numbers this gathers is via
EXPLAIN (ANALYZE, BUFFERS), but the plan is to add visibility through
the stats collector and pg_stat_statements in subsequent patches.
Ants Aasma, reviewed by Greg Smith, with some further changes by me.
Fix loss of previous expression-simplification work when a transform
function fires: we must not simply revert to untransformed input tree.
Instead build a dummy FuncExpr node to pass to the transform function.
This has the additional advantage of providing a simpler, more uniform
API for transform functions.
Move documentation to a somewhat less buried spot, relocate some
poorly-placed code, be more wary of null constants and invalid typmod
values, add an opr_sanity check on protransform function signatures,
and some other minor cosmetic adjustments.
Note: although this patch touches pg_proc.h, no need for catversion
bump, because the changes are cosmetic and don't actually change the
intended catalog contents.
Per a suggestion from Euler Taveira, it seems like a good idea to include
this information in \du (and \dg) output. This costs nothing for people
who are not using the VALID UNTIL feature, while for those who are, it's
rather critical information.
Fabrízio de Royes Mello
PGAC_PATH_COLLATEINDEX supposed that it could use AC_PATH_PROGS to search
for collateindex.pl, but that macro will only accept files that are marked
executable, and at least some DocBook installations don't mark the script
executable (a case the docs Makefile was already prepared for). Accept the
script if it's present and readable in $DOCBOOKSTYLE/bin, and otherwise
search the PATH as before.
Having fixed that up, we don't need the fallback case that was in the docs
Makefile, and instead can throw an understandable error if configure didn't
find the script. Per recent trouble report from John Lumby.
Document that routine vacuuming is now also important for the purpose
of index-only scans; and mention in the section that describes the
visibility map that it is used to implement index-only scans.
Marti Raudsepp, with some changes by me.
Instead of just stopping after removing an arbitrary subset of orphaned
large objects, commit and start a new transaction after each -l objects.
This is just as effective as the original patch at limiting the number of
locks used, and it doesn't require doing the OID collection process
repeatedly to get everything. Since the option no longer changes the
fundamental behavior of vacuumlo, and it avoids a known server-side
limitation, enable it by default (with a default limit of 1000 LOs per
transaction).
In passing, be more careful about properly quoting the names of tables
and fields, and do some other cosmetic cleanup.
This is intended as infrastructure to allow sepgsql to cooperate with
connection pooling software, by allowing the effective security label
to be set for each new connection.
KaiGai Kohei, reviewed by Yeb Havinga.
add ability to control permissions of created files
have psql echo its queries for easier debugging
output four separate log files, and delete them on success
add -r/--retain option to keep log files after success
make logs file append-only
remove -g/-G/-l logging options
sugggest tailing appropriate log file on failure
enhance -v/--verbose behavior
This patch fixes the other major compatibility-breaking limitation of
SPGiST, that it didn't store anything for null values of the indexed
column, and so could not support whole-index scans or "x IS NULL"
tests. The approach is to create a wholly separate search tree for
the null entries, and use fixed "allTheSame" insertion and search
rules when processing this tree, instead of calling the index opclass
methods. This way the opclass methods do not need to worry about
dealing with nulls.
Catversion bump is for pg_am updates as well as the change in on-disk
format of SPGiST indexes; there are some tweaks in SPGiST WAL records
as well.
Heavily rewritten version of a patch by Oleg Bartunov and Teodor Sigaev.
(The original also stored nulls separately, but it reused GIN code to do
so; which required undesirable compromises in the on-disk format, and
would likely lead to bugs due to the GIN code being required to work in
two very different contexts.)
The original API definition was incapable of supporting whole-index scans
because there was no way to invoke leaf-value reconstruction without
checking any qual conditions. Also, it was inefficient for
multiple-qual-condition scans because value reconstruction got done over
again for each qual condition, and because other internal work in the
consistent functions likewise had to be done for each qual. To fix these
issues, pass the whole scankey array to the opclass consistent functions,
instead of only letting them see one item at a time. (Essentially, the
loop over scankey entries is now inside the consistent functions not
outside them. This makes the consistent functions a bit more complicated,
but not unreasonably so.)
In itself this commit does nothing except save a few cycles in
multiple-qual-condition index scans, since we can't support whole-index
scans on SPGiST indexes until nulls are included in the index. However,
I consider this a must-fix for 9.2 because once we release it will get
very much harder to change the opclass API definition.
Further reflection shows that a single callback isn't very workable if we
desire to let FDWs generate multiple Paths, because that forces the FDW to
do all work necessary to generate a valid Plan node for each Path. Instead
split the former PlanForeignScan API into three steps: GetForeignRelSize,
GetForeignPaths, GetForeignPlan. We had already bit the bullet of breaking
the 9.1 FDW API for 9.2, so this shouldn't cause very much additional pain,
and it's substantially more flexible for complex FDWs.
Add an fdw_private field to RelOptInfo so that the new functions can save
state there rather than possibly having to recalculate information two or
three times.
In addition, we'd not thought through what would be needed to allow an FDW
to set up subexpressions of its choice for runtime execution. We could
treat ForeignScan.fdw_private as an executable expression but that seems
likely to break existing FDWs unnecessarily (in particular, it would
restrict the set of node types allowable in fdw_private to those supported
by expression_tree_walker). Instead, invent a separate field fdw_exprs
which will receive the postprocessing appropriate for expression trees.
(One field is enough since it can be a list of expressions; also, we assume
the corresponding expression state tree(s) will be held within fdw_state,
so we don't need to add anything to ForeignScanState.)
Per review of Hanada Shigeru's pgsql_fdw patch. We may need to tweak this
further as we continue to work on that patch, but to me it feels a lot
closer to being right now.
GetForeignColumnOptions provides some abstraction for accessing
column-specific FDW options, on a par with the access functions that were
already provided here for other FDW-related information.
Adjust file_fdw.c to use GetForeignColumnOptions instead of equivalent
hand-rolled code.
In addition, add some SGML documentation for the functions exported by
foreign.c that are meant for use by FDW authors.
(This is the fdw_helper portion of the proposed pgsql_fdw patch.)
Hanada Shigeru, reviewed by KaiGai Kohei
The original API specification only allowed an FDW to create a single
access path, which doesn't seem like a terribly good idea in hindsight.
Instead, move the responsibility for building the Path node and calling
add_path() into the FDW's PlanForeignScan function. Now, it can do that
more than once if appropriate. There is no longer any need for the
transient FdwPlan struct, so get rid of that.
Etsuro Fujita, Shigeru Hanada, Tom Lane
In backup.sgml, point out that you need to be using the logging collector
if you want to log messages from a failing archive_command script. (This
is an oversimplification, in that it will work without the collector as
long as you're not sending postmaster stderr to /dev/null; but it seems
like a good idea to encourage use of the collector to avoid problems
with multiple processes concurrently scribbling on one file.)
In config.sgml, do some wordsmithing of logging_collector discussion.
Per bug #6518 from Janning Vygen
Comparing two xlog locations are useful for example when calculating
replication lag.
Euler Taveira de Oliveira, reviewed by Fujii Masao, and some cleanups
from me
This patch improves selectivity estimation for the array <@, &&, and @>
(containment and overlaps) operators. It enables collection of statistics
about individual array element values by ANALYZE, and introduces
operator-specific estimators that use these stats. In addition,
ScalarArrayOpExpr constructs of the forms "const = ANY/ALL (array_column)"
and "const <> ANY/ALL (array_column)" are estimated by treating them as
variants of the containment operators.
Since we still collect scalar-style stats about the array values as a
whole, the pg_stats view is expanded to show both these stats and the
array-style stats in separate columns. This creates an incompatible change
in how stats for tsvector columns are displayed in pg_stats: the stats
about lexemes are now displayed in the array-related columns instead of the
original scalar-related columns.
There are a few loose ends here, notably that it'd be nice to be able to
suppress either the scalar-style stats or the array-element stats for
columns for which they're not useful. But the patch is in good enough
shape to commit for wider testing.
Alexander Korotkov, reviewed by Noah Misch and Nathan Boley
The only reason this didn't work before was that parserOpenTable()
rejects composite types. So use relation_openrv() directly and
manually do the errposition() setup that parserOpenTable() does.
For those of us who prefer the formatting of the docs using the
website stylesheets. Use "make STYLE=website draft" (for example) to use.
The stylesheet itself is referenced directly to the website, so there
is currently no copy of it stored in the source repository. Thus, docs
built with it will only look correct if the browser can access the website
when viewing them.
The <literal> markup is not visible as distinct on man pages, which
creates a bit of confusion when looking at the documentation of the
pg_basebackup -l option. Rather than reinventing the entire font
system for man pages to remedy this, just put some quotes around this
particular case, which should also help in other output formats.
Several places were still written as though standard_conforming_strings
didn't exist, much less be the default. Now that it is on by default,
we can simplify the text and just insert occasional notes suggesting that
you might have to think harder if it's turned off. Per discussion of a
suggestion from Hannes Frederic Sowa.
Back-patch to 9.1 where standard_conforming_strings was made the default.
Most people won't read them individually anyway, it's an easy way to find
them, and it's a lot of duplicated information if they are kept in two
different places.
This makes it easier to match a column name with the description of it,
and makes it possible to add more detailed documentation in the future.
This patch does not add that extra documentation at this point, only
the structure required for it.
Modeled on the changes already done to pg_stat_activity.
