This introduces the following SQL/JSON functions for querying JSON
data using jsonpath expressions:
JSON_EXISTS(), which can be used to apply a jsonpath expression to a
JSON value to check if it yields any values.
JSON_QUERY(), which can be used to to apply a jsonpath expression to
a JSON value to get a JSON object, an array, or a string. There are
various options to control whether multi-value result uses array
wrappers and whether the singleton scalar strings are quoted or not.
JSON_VALUE(), which can be used to apply a jsonpath expression to a
JSON value to return a single scalar value, producing an error if it
multiple values are matched.
Both JSON_VALUE() and JSON_QUERY() functions have options for
handling EMPTY and ERROR conditions, which can be used to specify
the behavior when no values are matched and when an error occurs
during jsonpath evaluation, respectively.
Author: Nikita Glukhov <n.gluhov@postgrespro.ru>
Author: Teodor Sigaev <teodor@sigaev.ru>
Author: Oleg Bartunov <obartunov@gmail.com>
Author: Alexander Korotkov <aekorotkov@gmail.com>
Author: Andrew Dunstan <andrew@dunslane.net>
Author: Amit Langote <amitlangote09@gmail.com>
Author: Peter Eisentraut <peter@eisentraut.org>
Author: Jian He <jian.universality@gmail.com>
Reviewers have included (in no particular order):
Andres Freund, Alexander Korotkov, Pavel Stehule, Andrew Alsup,
Erik Rijkers, Zihong Yu, Himanshu Upadhyaya, Daniel Gustafsson,
Justin Pryzby, Álvaro Herrera, Jian He, Anton A. Melnikov,
Nikita Malakhov, Peter Eisentraut, Tomas Vondra
Discussion: https://postgr.es/m/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru
Discussion: https://postgr.es/m/20220616233130.rparivafipt6doj3@alap3.anarazel.de
Discussion: https://postgr.es/m/abd9b83b-aa66-f230-3d6d-734817f0995d%40postgresql.org
Discussion: https://postgr.es/m/CA+HiwqHROpf9e644D8BRqYvaAPmgBZVup-xKMDPk-nd4EpgzHw@mail.gmail.com
Discussion: https://postgr.es/m/CA+HiwqE4XTdfb1nW=Ojoy_tQSRhYt-q_kb6i5d4xcKyrLC1Nbg@mail.gmail.com
Since C99, there can be a trailing comma after the last value in an
enum definition. A lot of new code has been introducing this style on
the fly. Some new patches are now taking an inconsistent approach to
this. Some add the last comma on the fly if they add a new last
value, some are trying to preserve the existing style in each place,
some are even dropping the last comma if there was one. We could
nudge this all in a consistent direction if we just add the trailing
commas everywhere once.
I omitted a few places where there was a fixed "last" value that will
always stay last. I also skipped the header files of libpq and ecpg,
in case people want to use those with older compilers. There were
also a small number of cases where the enum type wasn't used anywhere
(but the enum values were), which ended up confusing pgindent a bit,
so I left those alone.
Discussion: https://www.postgresql.org/message-id/flat/386f8c45-c8ac-4681-8add-e3b0852c1620%40eisentraut.org
This commit introduces the SQL/JSON standard-conforming constructors for
JSON types:
JSON_ARRAY()
JSON_ARRAYAGG()
JSON_OBJECT()
JSON_OBJECTAGG()
Most of the functionality was already present in PostgreSQL-specific
functions, but these include some new functionality such as the ability
to skip or include NULL values, and to allow duplicate keys or throw
error when they are found, as well as the standard specified syntax to
specify output type and format.
Author: Nikita Glukhov <n.gluhov@postgrespro.ru>
Author: Teodor Sigaev <teodor@sigaev.ru>
Author: Oleg Bartunov <obartunov@gmail.com>
Author: Alexander Korotkov <aekorotkov@gmail.com>
Author: Amit Langote <amitlangote09@gmail.com>
Reviewers have included (in no particular order) Andres Freund, Alexander
Korotkov, Pavel Stehule, Andrew Alsup, Erik Rijkers, Zihong Yu,
Himanshu Upadhyaya, Daniel Gustafsson, Justin Pryzby.
Discussion: https://postgr.es/m/CAF4Au4w2x-5LTnN_bxky-mq4=WOqsGsxSpENCzHRAzSnEd8+WQ@mail.gmail.com
Discussion: https://postgr.es/m/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru
Discussion: https://postgr.es/m/20220616233130.rparivafipt6doj3@alap3.anarazel.de
Discussion: https://postgr.es/m/abd9b83b-aa66-f230-3d6d-734817f0995d%40postgresql.org
The previous macro implementations just cast the argument to a target
type but did not check whether the input type was appropriate. The
function implementation can do better type checking of the input type.
For the *GetDatumFast() macros, converting to an inline function
doesn't work in the !USE_FLOAT8_BYVAL case, but we can use
AssertVariableIsOfTypeMacro() to get a similar level of type checking.
Reviewed-by: Aleksander Alekseev <aleksander@timescale.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/8528fb7e-0aa2-6b54-85fb-0c0886dbd6ed%40enterprisedb.com
Make sure that function declarations use names that exactly match the
corresponding names from function definitions in optimizer, parser,
utility, libpq, and "commands" code, as well as in remaining library
code. Do the same for all code related to frontend programs (with the
exception of pg_dump/pg_dumpall related code).
Like other recent commits that cleaned up function parameter names, this
commit was written with help from clang-tidy. Later commits will handle
ecpg and pg_dump/pg_dumpall.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/CAH2-WznJt9CMM9KJTMjJh_zbL5hD9oX44qdJ4aqZtjFi-zA3Tg@mail.gmail.com
The reverts the following and makes some associated cleanups:
commit f79b803dc: Common SQL/JSON clauses
commit f4fb45d15: SQL/JSON constructors
commit 5f0adec25: Make STRING an unreserved_keyword.
commit 33a377608: IS JSON predicate
commit 1a36bc9db: SQL/JSON query functions
commit 606948b05: SQL JSON functions
commit 49082c2cc: RETURNING clause for JSON() and JSON_SCALAR()
commit 4e34747c8: JSON_TABLE
commit fadb48b00: PLAN clauses for JSON_TABLE
commit 2ef6f11b0: Reduce running time of jsonb_sqljson test
commit 14d3f24fa: Further improve jsonb_sqljson parallel test
commit a6baa4bad: Documentation for SQL/JSON features
commit b46bcf7a4: Improve readability of SQL/JSON documentation.
commit 112fdb352: Fix finalization for json_objectagg and friends
commit fcdb35c32: Fix transformJsonBehavior
commit 4cd8717af: Improve a couple of sql/json error messages
commit f7a605f63: Small cleanups in SQL/JSON code
commit 9c3d25e17: Fix JSON_OBJECTAGG uniquefying bug
commit a79153b7a: Claim SQL standard compliance for SQL/JSON features
commit a1e7616d6: Rework SQL/JSON documentation
commit 8d9f9634e: Fix errors in copyfuncs/equalfuncs support for JSON node types.
commit 3c633f32b: Only allow returning string types or bytea from json_serialize
commit 67b26703b: expression eval: Fix EEOP_JSON_CONSTRUCTOR and EEOP_JSONEXPR size.
The release notes are also adjusted.
Backpatch to release 15.
Discussion: https://postgr.es/m/40d2c882-bcac-19a9-754d-4299e1d87ac7@postgresql.org
This Patch introduces three SQL standard JSON functions:
JSON() (incorrectly mentioned in my commit message for f4fb45d15c)
JSON_SCALAR()
JSON_SERIALIZE()
JSON() produces json values from text, bytea, json or jsonb values, and
has facilitites for handling duplicate keys.
JSON_SCALAR() produces a json value from any scalar sql value, including
json and jsonb.
JSON_SERIALIZE() produces text or bytea from input which containis or
represents json or jsonb;
For the most part these functions don't add any significant new
capabilities, but they will be of use to users wanting standard
compliant JSON handling.
Nikita Glukhov
Reviewers have included (in no particular order) Andres Freund, Alexander
Korotkov, Pavel Stehule, Andrew Alsup, Erik Rijkers, Zihong Yu,
Himanshu Upadhyaya, Daniel Gustafsson, Justin Pryzby.
Discussion: https://postgr.es/m/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru
This introduces the SQL/JSON functions for querying JSON data using
jsonpath expressions. The functions are:
JSON_EXISTS()
JSON_QUERY()
JSON_VALUE()
All of these functions only operate on jsonb. The workaround for now is
to cast the argument to jsonb.
JSON_EXISTS() tests if the jsonpath expression applied to the jsonb
value yields any values. JSON_VALUE() must return a single value, and an
error occurs if it tries to return multiple values. JSON_QUERY() must
return a json object or array, and there are various WRAPPER options for
handling scalar or multi-value results. Both these functions have
options for handling EMPTY and ERROR conditions.
Nikita Glukhov
Reviewers have included (in no particular order) Andres Freund, Alexander
Korotkov, Pavel Stehule, Andrew Alsup, Erik Rijkers, Zihong Yu,
Himanshu Upadhyaya, Daniel Gustafsson, Justin Pryzby.
Discussion: https://postgr.es/m/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru
This patch introduces the SQL/JSON standard constructors for JSON:
JSON()
JSON_ARRAY()
JSON_ARRAYAGG()
JSON_OBJECT()
JSON_OBJECTAGG()
For the most part these functions provide facilities that mimic
existing json/jsonb functions. However, they also offer some useful
additional functionality. In addition to text input, the JSON() function
accepts bytea input, which it will decode and constuct a json value from.
The other functions provide useful options for handling duplicate keys
and null values.
This series of patches will be followed by a consolidated documentation
patch.
Nikita Glukhov
Reviewers have included (in no particular order) Andres Freund, Alexander
Korotkov, Pavel Stehule, Andrew Alsup, Erik Rijkers, Zihong Yu,
Himanshu Upadhyaya, Daniel Gustafsson, Justin Pryzby.
Discussion: https://postgr.es/m/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru
SQL/JSON standard allows manipulation with datetime values. So, it appears to
be convinient to allow datetime values to be represented in JsonbValue struct.
These datetime values are allowed for temporary representation only. During
serialization datetime values are converted into strings.
SQL/JSON requires writing timestamps with timezone in the same timezone offset
as they were parsed. This is why we allow storage of timezone offset in
JsonbValue struct. For the same reason timezone offset argument is added to
JsonEncodeDateTime() function.
Extracted from original patch by Nikita Glukhov, Teodor Sigaev, Oleg Bartunov.
Revised by me. Comments were adjusted by Liudmila Mantrova.
Discussion: https://postgr.es/m/fcc6fc6a-b497-f39a-923d-aa34d0c588e8%402ndQuadrant.com
Discussion: https://postgr.es/m/CAPpHfdsZgYEra_PeCLGNoXOWYx6iU-S3wF8aX0ObQUcZU%2B4XTw%40mail.gmail.com
Author: Nikita Glukhov, Teodor Sigaev, Oleg Bartunov, Alexander Korotkov, Liudmila Mantrova
Reviewed-by: Anastasia Lubennikova, Peter Eisentraut
The new function stashes its output value in a JsonbValue that can be
passed in by the caller, which enables some of them to pass
stack-allocated structs -- saving palloc cycles. It also allows some
callers that know they are handling a jsonb object to use this new jsonb
object-specific API, instead of going through generic container
findJsonbValueFromContainer.
Author: Nikita Glukhov
Discussion: https://postgr.es/m/7c417f90-f95f-247e-ba63-d95e39c0ad14@postgrespro.ru
This commit makes existing GIN operator classes jsonb_ops and json_path_ops
support "jsonb @@ jsonpath" and "jsonb @? jsonpath" operators. Basic idea is
to extract statements of following form out of jsonpath.
key1.key2. ... .keyN = const
The rest of jsonpath is rechecked from heap.
Catversion is bumped.
Discussion: https://postgr.es/m/fcc6fc6a-b497-f39a-923d-aa34d0c588e8%402ndQuadrant.com
Author: Nikita Glukhov, Alexander Korotkov
Reviewed-by: Jonathan Katz, Pavel Stehule
SQL 2016 standards among other things contains set of SQL/JSON features for
JSON processing inside of relational database. The core of SQL/JSON is JSON
path language, allowing access parts of JSON documents and make computations
over them. This commit implements partial support JSON path language as
separate datatype called "jsonpath". The implementation is partial because
it's lacking datetime support and suppression of numeric errors. Missing
features will be added later by separate commits.
Support of SQL/JSON features requires implementation of separate nodes, and it
will be considered in subsequent patches. This commit includes following
set of plain functions, allowing to execute jsonpath over jsonb values:
* jsonb_path_exists(jsonb, jsonpath[, jsonb, bool]),
* jsonb_path_match(jsonb, jsonpath[, jsonb, bool]),
* jsonb_path_query(jsonb, jsonpath[, jsonb, bool]),
* jsonb_path_query_array(jsonb, jsonpath[, jsonb, bool]).
* jsonb_path_query_first(jsonb, jsonpath[, jsonb, bool]).
This commit also implements "jsonb @? jsonpath" and "jsonb @@ jsonpath", which
are wrappers over jsonpath_exists(jsonb, jsonpath) and jsonpath_predicate(jsonb,
jsonpath) correspondingly. These operators will have an index support
(implemented in subsequent patches).
Catversion bumped, to add new functions and operators.
Code was written by Nikita Glukhov and Teodor Sigaev, revised by me.
Documentation was written by Oleg Bartunov and Liudmila Mantrova. The work
was inspired by Oleg Bartunov.
Discussion: https://postgr.es/m/fcc6fc6a-b497-f39a-923d-aa34d0c588e8%402ndQuadrant.com
Author: Nikita Glukhov, Teodor Sigaev, Alexander Korotkov, Oleg Bartunov, Liudmila Mantrova
Reviewed-by: Tomas Vondra, Andrew Dunstan, Pavel Stehule, Alexander Korotkov
By project convention, these names should include "P" when dealing with a
pointer type; that is, if the result of a GETARG macro is of type FOO *,
it should be called PG_GETARG_FOO_P not just PG_GETARG_FOO. Some newer
types such as JSONB and ranges had not followed the convention, and a
number of contrib modules hadn't gotten that memo either. Rename the
offending macros to improve consistency.
In passing, fix a few places that thought PG_DETOAST_DATUM() returns
a Datum; it does not, it returns "struct varlena *". Applying
DatumGetPointer to that happens not to cause any bad effects today,
but it's formally wrong. Also, adjust an ltree macro that was designed
without any thought for what pgindent would do with it.
This is all cosmetic and shouldn't have any impact on generated code.
Mark Dilger, some further tweaks by me
Discussion: https://postgr.es/m/EA5676F4-766F-4F38-8348-ECC7DB427C6A@gmail.com
This will be useful for hash partitioning, which needs a way to seed
the hash functions to avoid problems such as a hash index on a hash
partitioned table clumping all values into a small portion of the
bucket space; it's also useful for anything that wants a 64-bit hash
value rather than a 32-bit hash value.
Just in case somebody wants a 64-bit hash value that is compatible
with the existing 32-bit hash values, make the low 32-bits of the
64-bit hash value match the 32-bit hash value when the seed is 0.
Robert Haas and Amul Sul
Discussion: http://postgr.es/m/CA+Tgmoafx2yoJuhCQQOL5CocEi-w_uG4S2xT0EtgiJnPGcHW3g@mail.gmail.com
Change pg_bsd_indent to follow upstream rules for placement of comments
to the right of code, and remove pgindent hack that caused comments
following #endif to not obey the general rule.
Commit e3860ffa4dd0dad0dd9eea4be9cc1412373a8c89 wasn't actually using
the published version of pg_bsd_indent, but a hacked-up version that
tried to minimize the amount of movement of comments to the right of
code. The situation of interest is where such a comment has to be
moved to the right of its default placement at column 33 because there's
code there. BSD indent has always moved right in units of tab stops
in such cases --- but in the previous incarnation, indent was working
in 8-space tab stops, while now it knows we use 4-space tabs. So the
net result is that in about half the cases, such comments are placed
one tab stop left of before. This is better all around: it leaves
more room on the line for comment text, and it means that in such
cases the comment uniformly starts at the next 4-space tab stop after
the code, rather than sometimes one and sometimes two tabs after.
Also, ensure that comments following #endif are indented the same
as comments following other preprocessor commands such as #else.
That inconsistency turns out to have been self-inflicted damage
from a poorly-thought-through post-indent "fixup" in pgindent.
This patch is much less interesting than the first round of indent
changes, but also bulkier, so I thought it best to separate the effects.
Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org
Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
This improves readability a bit and may make future improvements easier.
In passing, make sure that the JB_ROOT_IS_XXX macros deliver boolean (0/1)
results; the previous coding was a bug hazard, though no actual bugs are
known.
Nikita Glukhov, extended a bit by me
Discussion: https://postgr.es/m/9e21a39c-c1d7-b9b5-44a0-c5345a5029f6@postgrespro.ru
Gen_fmgrtab.pl creates a new file fmgrprotos.h, which contains
prototypes for all functions registered in pg_proc.h. This avoids
having to manually maintain these prototypes across a random variety of
header files. It also automatically enforces a correct function
signature, and since there are warnings about missing prototypes, it
will detect functions that are defined but not registered in
pg_proc.h (or otherwise used).
Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
It inserts a new value into an jsonb array at arbitrary position or
a new key to jsonb object.
Author: Dmitry Dolgov
Reviewers: Petr Jelinek, Vitaly Burovoy, Andrew Dunstan
The function is given a fourth parameter, which defaults to true. When
this parameter is true, if the last element of the path is missing
in the original json, jsonb_set creates it in the result and assigns it
the new value. If it is false then the function does nothing unless all
elements of the path are present, including the last.
Based on some original code from Dmitry Dolgov, heavily modified by me.
Catalog version bumped.
Remove a bunch of "extern Datum foo(PG_FUNCTION_ARGS);" declarations that
are no longer needed now that PG_FUNCTION_INFO_V1(foo) provides that.
Some of these were evidently missed in commit e7128e8dbb305059, but others
were cargo-culted in in code added since then. Possibly that can be blamed
in part on the fact that we'd not fixed relevant documentation examples,
which I've now done.
pushJsonbValue was accepting jbvBinary objects passed as WJB_ELEM or
WJB_VALUE data. While this succeeded, when those objects were later
encountered in attempting to convert the result to Jsonb, errors
occurred. With this change we ghuarantee that a JSonbValue constructed
from calls to pushJsonbValue does not contain any jbvBinary objects.
This cures a problem observed with jsonb_delete.
This means callers of pushJsonbValue no longer need to perform this
unpacking themselves. A subsequent patch will perform some cleanup in
that area.
The error was not triggered by any 9.4 code, but this is a publicly
visible routine, and so the error could be exercised by third party
code, therefore backpatch to 9.4.
Bug report from Peter Geoghegan, fix by me.
jsonb_pretty(jsonb) produces nicely indented json output.
jsonb || jsonb concatenates two jsonb values.
jsonb - text removes a key and its associated value from the json
jsonb - int removes the designated array element
jsonb - text[] removes a key and associated value or array element at
the designated path
jsonb_replace(jsonb,text[],jsonb) replaces the array element designated
by the path or the value associated with the key designated by the path
with the given value.
Original work by Dmitry Dolgov, adapted and reworked for PostgreSQL core
by Andrew Dunstan, reviewed and tidied up by Petr Jelinek.
Replace some bogus "x[1]" declarations with "x[FLEXIBLE_ARRAY_MEMBER]".
Aside from being more self-documenting, this should help prevent bogus
warnings from static code analyzers and perhaps compiler misoptimizations.
This patch is just a down payment on eliminating the whole problem, but
it gets rid of a lot of easy-to-fix cases.
Note that the main problem with doing this is that one must no longer rely
on computing sizeof(the containing struct), since the result would be
compiler-dependent. Instead use offsetof(struct, lastfield). Autoconf
also warns against spelling that offsetof(struct, lastfield[0]).
Michael Paquier, review and additional fixes by me.
The functions are:
to_jsonb()
jsonb_object()
jsonb_build_object()
jsonb_build_array()
jsonb_agg()
jsonb_object_agg()
Also along the way some better logic is implemented in
json_categorize_type() to match that in the newly implemented
jsonb_categorize_type().
Andrew Dunstan, reviewed by Pavel Stehule and Alvaro Herrera.
The original design used an array of offsets into the variable-length
portion of a JSONB container. However, such an array is basically
uncompressible by simple compression techniques such as TOAST's LZ
compressor. That's bad enough, but because the offset array is at the
front, it tended to trigger the give-up-after-1KB heuristic in the TOAST
code, so that the entire JSONB object was stored uncompressed; which was
the root cause of bug #11109 from Larry White.
To fix without losing the ability to extract a random array element in O(1)
time, change this scheme so that most of the JEntry array elements hold
lengths rather than offsets. With data that's compressible at all, there
tend to be fewer distinct element lengths, so that there is scope for
compression of the JEntry array. Every N'th entry is still an offset.
To determine the length or offset of any specific element, we might have
to examine up to N preceding JEntrys, but that's still O(1) so far as the
total container size is concerned. Testing shows that this cost is
negligible compared to other costs of accessing a JSONB field, and that
the method does largely fix the incompressible-data problem.
While at it, rearrange the order of elements in a JSONB object so that
it's "all the keys, then all the values" not alternating keys and values.
This doesn't really make much difference right at the moment, but it will
allow providing a fast path for extracting individual object fields from
large JSONB values stored EXTERNAL (ie, uncompressed), analogously to the
existing optimization for substring extraction from large EXTERNAL text
values.
Bump catversion to denote the incompatibility in on-disk format.
We will need to fix pg_upgrade to disallow upgrading jsonb data stored
with 9.4 betas 1 and 2.
Heikki Linnakangas and Tom Lane
There's no longer much pressure to switch the default GIN opclass for
jsonb, but there was still some unhappiness with the name "jsonb_hash_ops",
since hashing is no longer a distinguishing property of that opclass,
and anyway it seems like a relatively minor detail. At the suggestion of
Heikki Linnakangas, we'll use "jsonb_path_ops" instead; that captures the
important characteristic that each index entry depends on the entire path
from the document root to the indexed value.
Also add a user-facing explanation of the implementation properties of
these two opclasses.
Fix JSONB_MAX_ELEMS and JSONB_MAX_PAIRS macros to use CB_MASK in the
calculation. JENTRY_POSMASK happens to have the same value at the moment,
but that's just coincidental.
Refactor jsonb iterator functions, for readability.
Get rid of the JENTRY_ISFIRST flag. Whenever we handle JEntrys, we have
access to the whole array and have enough context information to know
which entry is the first. This frees up one bit in the JEntry header for
future use. While we're at it, shuffle the JEntry bits so that boolean
true and false go together, for aesthetic reasons.
Bump catalog version as this changes the on-disk format slightly.
