I was able to crash postgres 6.5.3 when I did an 'alter user' command.
After I started a debugger I found the problem in the timezone handling
of
datetime (my Linux box lost its timezone information, that's how the
problem occurred).
Only 7 bytes are reserved for the timezone, without checking for
boundaries.
Attached is a patch that fixes this problem and emits a NOTICE if a
timezone is encountered that is longer than MAXTZLEN bytes, like this:
Jeroen van Vianen
Make all system indexes unique.
Make all cache loads use system indexes.
Rename *rel to *relid in inheritance tables.
Rename cache names to be clearer.
for the case of errors in backend startup, and proc_exit's method for
coping with errors during proc_exit was *completely* busted. Fixed per
discussions on pghackers around 11/6/99.
inval.c thought it could safely use the catcache to look up the OIDs of
system relations. Not good, considering that inval.c could be called
during catcache loading, if a shared-inval message arrives. Rip out the
lookup logic and instead use the known OIDs from pg_class.h.
Warn_restart has been set by the backend main loop. This means that
elog(ERROR) or elog(FATAL) in the postmaster or during backend startup
now have well-defined behavior: proc_exit() rather than coredump.
In the case of elog() inside the postmaster, I think that proc_exit()
is probably not enough --- don't we want our child backends to be
forced to quit too? But I don't understand Vadim's recent changes in
this area, so I'll leave it to him to look over and tweak if needed.
subselects can only appear on the righthand side of a binary operator.
That's still true for quantified predicates like x = ANY (SELECT ...),
but a subselect that delivers a single result can now appear anywhere
in an expression. This is implemented by changing EXPR_SUBLINK sublinks
to represent just the (SELECT ...) expression, without any 'left hand
side' or combining operator --- so they're now more like EXISTS_SUBLINK.
To handle the case of '(x, y, z) = (SELECT ...)', I added a new sublink
type MULTIEXPR_SUBLINK, which acts just like EXPR_SUBLINK used to.
But the grammar will only generate one for a multiple-left-hand-side
row expression.
Now indexes of pg_class and pg_type are unique indexes
and guarantee the uniqueness of correponding attributes.
heap_create() was changed to take another boolean parameter
which allows to postpone the creation of disk file.
The name of rd_nonameunlinked was changed to rd_unlinked.
It is used generally(not only for noname relations) now.
Requires initdb.
during initial run formation by keeping both current run and next-run
tuples in the same heap (yup, Knuth is smarter than I am). And, during
merge passes, make use of available sort memory to load multiple tuples
from any one input 'tape' at a time, thereby improving locality of
access to the temp file.
eliminating some wildly inconsistent coding in various parts of the
system. I set MAXPGPATH = 1024 in config.h.in. If anyone is really
convinced that there ought to be a configure-time test to set the
value, go right ahead ... but I think it's a waste of time.
a generalized module 'tuplesort.c' that can sort either HeapTuples or
IndexTuples, and is not tied to execution of a Sort node. Clean up
memory leakages in sorting, and replace nbtsort.c's private implementation
of mergesorting with calls to tuplesort.c.
recycle storage within sort temp file on a block-by-block basis. This
reduces peak disk usage to essentially just the volume of data being
sorted, whereas it had been about 4x the data volume before.
BufFile so that it handles multi-segment temporary files transparently.
This allows sorts and hashes to work with data exceeding 2Gig (or whatever
the local limit on file size is). Change psort.c to use relative seeks
instead of absolute seeks for backwards scanning, so that it won't fail
when the data volume exceeds 2Gig.
