The new format accepts exactly the same data as the json type. However, it is
stored in a format that does not require reparsing the orgiginal text in order
to process it, making it much more suitable for indexing and other operations.
Insignificant whitespace is discarded, and the order of object keys is not
preserved. Neither are duplicate object keys kept - the later value for a given
key is the only one stored.
The new type has all the functions and operators that the json type has,
with the exception of the json generation functions (to_json, json_agg etc.)
and with identical semantics. In addition, there are operator classes for
hash and btree indexing, and two classes for GIN indexing, that have no
equivalent in the json type.
This feature grew out of previous work by Oleg Bartunov and Teodor Sigaev, which
was intended to provide similar facilities to a nested hstore type, but which
in the end proved to have some significant compatibility issues.
Authors: Oleg Bartunov, Teodor Sigaev, Peter Geoghegan and Andrew Dunstan.
Review: Andres Freund
The length of the output buffer was calculated based on the size of the
argument hstore. On a sizeof(int) == 4 platform and a huge argument, it
could overflow, causing a too small buffer to be allocated.
Refactor the function to use a StringInfo instead of pre-allocating the
buffer. Makes it shorter and more readable, too.
Several functions, mostly type input functions, calculated an allocation
size such that the calculation wrapped to a small positive value when
arguments implied a sufficiently-large requirement. Writes past the end
of the inadvertent small allocation followed shortly thereafter.
Coverity identified the path_in() vulnerability; code inspection led to
the rest. In passing, add check_stack_depth() to prevent stack overflow
in related functions.
Back-patch to 8.4 (all supported versions). The non-comment hstore
changes touch code that did not exist in 8.4, so that part stops at 9.0.
Noah Misch and Heikki Linnakangas, reviewed by Tom Lane.
Security: CVE-2014-0064
Make slightly better decisions about indentation than what pgindent
is capable of. Mostly breaking out long function calls into one
line per argument, with a few other minor adjustments.
No functional changes- all whitespace.
pgindent ran cleanly (didn't change anything) after.
Passes all regressions.
This adds the following:
json_agg(anyrecord) -> json
to_json(any) -> json
hstore_to_json(hstore) -> json (also used as a cast)
hstore_to_json_loose(hstore) -> json
The last provides heuristic treatment of numbers and booleans.
Also, in json generation, if any non-builtin type has a cast to json,
that function is used instead of the type's output function.
Andrew Dunstan, reviewed by Steve Singer.
Catalog version bumped.
This reduces unnecessary exposure of other headers through htup.h, which
is very widely included by many files.
I have chosen to move the function prototypes to the new file as well,
because that means htup.h no longer needs to include tupdesc.h. In
itself this doesn't have much effect in indirect inclusion of tupdesc.h
throughout the tree, because it's also required by execnodes.h; but it's
something to explore in the future, and it seemed best to do the htup.h
change now while I'm busy with it.
The Solaris Studio compiler warns about these instances, unlike more
mainstream compilers such as gcc. But manual inspection showed that
the code is clearly not reachable, and we hope no worthy compiler will
complain about removing this code.
The latter was already the dominant use, and it's preferable because
in C the convention is that intXX means XX bits. Therefore, allowing
mixed use of int2, int4, int8, int16, int32 is obviously confusing.
Remove the typedefs for int2 and int4 for now. They don't seem to be
widely used outside of the PostgreSQL source tree, and the few uses
can probably be cleaned up by the time this ships.
This addresses only those cases that are easy to fix by adding or
moving a const qualifier or removing an unnecessary cast. There are
many more complicated cases remaining.
It appears that this will be faster for all but the shortest strings;
at least one some platforms, memcmp() can use word-at-a-time comparisons.
Noah Misch, somewhat pared down.
Remove the 64K limit on the lengths of keys and values within an hstore.
(This changes the on-disk format, but the old format can still be read.)
Add support for btree/hash opclasses for hstore --- this is not so much
for actual indexing purposes as to allow use of GROUP BY, DISTINCT, etc.
Add various other new functions and operators.
Andrew Gierth
unnecessary #include lines in it. Also, move some tuple routine prototypes and
macros to htup.h, which allows removal of heapam.h inclusion from some .c
files.
For this to work, a new header file access/sysattr.h needed to be created,
initially containing attribute numbers of system columns, for pg_dump usage.
While at it, make contrib ltree, intarray and hstore header files more
consistent with our header style.
ways. I'm not totally sure that I caught everything, but at least now they pass
their regression tests with VARSIZE/SET_VARSIZE defined to reverse byte order.
return true for exactly the characters treated as whitespace by their flex
scanners. Per report from Victor Snezhko and subsequent investigation.
Also fix a passel of unsafe usages of <ctype.h> functions, that is, ye olde
char-vs-unsigned-char issue. I won't miss <ctype.h> when we are finally
able to stop using it.
Andrew Dunstan
Heikki Linnakangas
Noah Misch
Peter Eisentraut
Stephen Frost
Bruce Momjian
Tom Lane
Alvaro Herrera
Robert Haas
Magnus Hagander
Teodor Sigaev
Neil Conway