of tuples when passing data up through multiple plan nodes. A slot can now
hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting
of Datum/isnull arrays. Upper plan levels can usually just copy the Datum
arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr()
calls to extract the data again. This work extends Atsushi Ogawa's earlier
patch, which provided the key idea of adding Datum arrays to TupleTableSlots.
(I believe however that something like this was foreseen way back in Berkeley
days --- see the old comment on ExecProject.) A test case involving many
levels of join of fairly wide tables (about 80 columns altogether) showed
about 3x overall speedup, though simple queries will probably not be
helped very much.
I have also duplicated some code in heaptuple.c in order to provide versions
of heap_formtuple and friends that use "bool" arrays to indicate null
attributes, instead of the old convention of "char" arrays containing either
'n' or ' '. This provides a better match to the convention used by
ExecEvalExpr. While I have not made a concerted effort to get rid of uses
of the old routines, I think they should be deprecated and eventually removed.
< o Disallow encodings like UTF8 which PostgreSQL supports
< but the operating system does not (already disallowed by
< pginstaller)
> o Add support for Unicode
< To fix UTF8, the data needs to be converted to UTF16 and then
< the Win32 wcscoll() can be used, and perhaps other functions
> To fix this, the data needs to be converted to/from UTF16/UTF8
> so the Win32 wcscoll() can be used, and perhaps other functions
< locales but provides no ordering.
<
> locales but provides no ordering or character set classes.
whether or not it is a security definer. Changing a function's strictness
is required by SQL2003, and the other capabilities make sense. Also, allow
an optional RESTRICT noise word to be specified, for SQL conformance.
Some trivial regression tests added and the documentation has been
updated.
can tell whether it is being used as an aggregate or not. This allows
such a function to avoid re-pallocing a pass-by-reference transition
value; normally it would be unsafe for a function to scribble on an input,
but in the aggregate case it's safe to reuse the old transition value.
Make int8inc() do this. This gets a useful improvement in the speed of
COUNT(*), at least on narrow tables (it seems to be swamped by I/O when
the table rows are wide). Per a discussion in early December with
Neil Conway. I also fixed int_aggregate.c to check this, thereby
turning it into something approaching a supportable technique instead
of being a crude hack.
Formerly, if such a clause contained no aggregate functions we mistakenly
treated it as equivalent to WHERE. Per spec it must cause the query to
be treated as a grouped query of a single group, the same as appearance
of aggregate functions would do. Also, the HAVING filter must execute
after aggregate function computation even if it itself contains no
aggregate functions.
the freelist, plus per-buffer spinlocks that protect access to individual
shared buffer headers. This requires abandoning a global freelist (since
the freelist is a global contention point), which shoots down ARC and 2Q
as well as plain LRU management. Adopt a clock sweep algorithm instead.
Preliminary results show substantial improvement in multi-backend situations.
adjusting values:
> But to be on the safe side, it would make sense to do something similar
> to the BSD section, and comment about older distributions maybe needing
> to manipulate /proc/kernel/* directly.
Mark Kirkwood
! authentication. Use of this environment variable is not
! recommended for security reasons (some operating systems
! allow non-root users to see process environment variables via
! <application>ps</>); instead consider using the
! <filename>~/.pgpass</> file (see <xref linkend="libpq-pgpass">).
< * Allow server configuration parameters to be remotely modified
> * Allow pg_hba.conf settings to be controlled via SQL
>
> This would require a new global table that is dumped to flat file for
> use by the postmaster. We do a similar thing for pg_shadow currently.
>
< * Consider use of open/fcntl(O_DIRECT) to minimize OS caching
> * Consider use of open/fcntl(O_DIRECT) to minimize OS caching,
> especially for WAL writes
in GetNewTransactionId(). Since the limit value has to be computed
before we run any real transactions, this requires adding code to database
startup to scan pg_database and determine the oldest datfrozenxid.
This can conveniently be combined with the first stage of an attack on
the problem that the 'flat file' copies of pg_shadow and pg_group are
not properly updated during WAL recovery. The code I've added to
startup resides in a new file src/backend/utils/init/flatfiles.c, and
it is responsible for rewriting the flat files as well as initializing
the XID wraparound limit value. This will eventually allow us to get
rid of GetRawDatabaseInfo too, but we'll need an initdb so we can add
a trigger to pg_database.
more variables can be found in the libpq manual section.
Mention .pgpass in the psql manual page section dealing with connection
parameters and point to the libpq section for more details.
Backpatch to 8.0.X.
the item:
< o Automatic failover
<
< The proper solution to this will probably the use of a master/slave
< replication solution like Sloney and a connection pooling tool like
< pgpool.
<
< all temporary tables, removal of any NOTIFYs, etc. This could be used
< for connection pooling. We could also change RESET ALL to have this
< functionality.
> all temporary tables, removal of any NOTIFYs, cursors, prepared
> queries(?), currval()s, etc. This could be used for connection pooling.
> We could also change RESET ALL to have this functionality.
tests. Contributed by Koju Iijima, review from Neil Conway, Gavin Sherry
and Tom Lane.
Also, fix error in description of WITH CHECK OPTION clause in the CREATE
VIEW reference page: it should be "CASCADED", not "CASCADE".