On closer inspection, that two-element initcond value seems to have been
a little white lie to avoid explaining the full behavior of float8_accum.
But if people are going to expect the examples to be exactly correct,
I suppose we'd better explain. Per comment from Thom Brown.
Recent versions of the Linux system header files cause xlogdefs.h to
believe that open_datasync should be the default sync method, whereas
formerly fdatasync was the default on Linux. open_datasync is a bad
choice, first because it doesn't actually outperform fdatasync (in fact
the reverse), and second because we try to use O_DIRECT with it, causing
failures on certain filesystems (e.g., ext4 with data=journal option).
This part of the patch is largely per a proposal from Marti Raudsepp.
More extensive changes are likely to follow in HEAD, but this is as much
change as we want to back-patch.
Also clean up confusing code and incorrect documentation surrounding the
fsync_writethrough option. Those changes shouldn't result in any actual
behavioral change, but I chose to back-patch them anyway to keep the
branches looking similar in this area.
In 9.0 and HEAD, also do some copy-editing on the WAL Reliability
documentation section.
Back-patch to all supported branches, since any of them might get used
on modern Linux versions.
The GRANT reference page failed to mention that the USAGE privilege
allows modifying associated user mappings, although this was already
documented on the CREATE/ALTER/DROP USER MAPPING pages.
In particular, we are now more explicit about the fact that you may need
wal_sync_method=fsync_writethrough for crash-safety on some platforms,
including MaxOS X. There's also now an explicit caution against assuming
that the default setting of wal_sync_method is either crash-safe or best
for performance.
There are numerous methods by which a Perl or Tcl function can subvert
the behavior of another such function executed later; for example, by
redefining standard functions or operators called by the target function.
If the target function is SECURITY DEFINER, or is called by such a
function, this means that any ordinary SQL user with Perl or Tcl language
usage rights can do essentially anything with the privileges of the target
function's owner.
To close this security hole, create a separate Perl or Tcl interpreter for
each SQL userid under which plperl or pltcl functions are executed within
a session. However, all plperlu or pltclu functions run within a session
still share a single interpreter, since they all execute at the trust
level of a database superuser anyway.
Note: this change results in a functionality loss when libperl has been
built without the "multiplicity" option: it's no longer possible to call
plperl functions under different userids in one session, since such a
libperl can't support multiple interpreters in one process. However, such
a libperl already failed to support concurrent use of plperl and plperlu,
so it's likely that few people use such versions with Postgres.
Security: CVE-2010-3433
parameter against server cert's CN field) to succeed in the case where
both host and hostaddr are specified. As with the existing precedents
for Kerberos, GSSAPI, SSPI, it is the calling application's responsibility
that host and hostaddr match up --- we just use the host name as given.
Per bug #5559 from Christopher Head.
In passing, make the error handling and messages for the no-host-name-given
failure more consistent among these four cases, and correct a lie in the
documentation: we don't attempt to reverse-lookup host from hostaddr
if host is missing.
Back-patch to 8.4 where SSL cert verification was introduced.
formats for geometric types. Per bug #5536 from Jon Strait, and my own
testing.
Back-patch to all supported branches, since this doco has been wrong right
along -- we certainly haven't changed the I/O behavior of these types in
many years.
In HEAD, emit a warning when an operator named => is defined.
In both HEAD and the backbranches (except in 8.2, where contrib
modules do not have documentation), document that hstore's text =>
text operator may be removed in a future release, and encourage the
use of the hstore(text, text) function instead. This function only
exists in HEAD (previously, it was called tconvert), so backpatch
it back to 8.2, when hstore was added. Per discussion.
to be initialized with proper values. Affected parameters are
fillfactor, analyze_threshold, and analyze_scale_factor.
Especially uninitialized fillfactor caused inefficient page usage
because we built a StdRdOptions struct in which fillfactor is zero
if any reloption is set for the toast table.
In addition, we disallow toast.autovacuum_analyze_threshold and
toast.autovacuum_analyze_scale_factor because we didn't actually
support them; they are always ignored.
Report by Rumko on pgsql-bugs on 12 May 2010.
Analysis by Tom Lane and Alvaro Herrera. Patch by me.
Backpatch to 8.4.
