[Django] #27478: JSONB_AGG is not available in PostgreSQL 9.4

[Django]

#27478: JSONB_AGG is not available in PostgreSQL 9.4
-------------------------------------+-------------------------------------
Reporter: Christian | Owner: nobody
von Roques |
Type: | Status: new
Cleanup/optimization |
Component: | Version: master
Uncategorized |
Severity: Normal | Keywords: JsonAgg JSONB_AGG
Triage Stage: | Has patch: 1
Unreviewed |
Needs documentation: 0 | Needs tests: 0
Patch needs improvement: 0 | Easy pickings: 0
UI/UX: 0 |
-------------------------------------+-------------------------------------
`django.contrib.postgres.aggregates.general.JsonAgg` uses `JSONB_AGG`. The
Django test-suite contains a test which fails due to `JSONB_AGG` being
unavailable as shown below when run against PostgreSQL 9.4. The test is
already marked as `@skipUnlessDBFeature('has_jsonb_datatype')`, but JSONB
became available with PostgreSQL 9.4 and `JSONB_AGG` was added in
PostgreSQL 9.5.
I currently see three possibilities:
1. Add a new feature `has_jsonb_agg` and make the test
`@skipUnlessDBFeature('has_jsonb_agg')`
2. Add a new feature `has_jsonb_agg` and use `JSON_AGG` instead of
`JSONB_AGG` when `JSONB_AGG` is unavailable.
3. Have `has_jsonb_datatype` lie about it not being available in
PostgreSQL 9.4.
I prefer and have implemented option 2 and really don't like option 3.

See my [https://github.com/roques/django/tree/jsonb_agg branch] for my
initial implementation. — Is there a cleaner way to achieve this besides
redefining `JsonAgg.as_sql`?

{{{
ERROR: test_json_agg (postgres_tests.test_aggregates.TestGeneralAggregate)
----------------------------------------------------------------------
Traceback (most recent call last):
File "/usr/lib/python3.4/unittest/case.py", line 58, in testPartExecutor
yield
File "/usr/lib/python3.4/unittest/case.py", line 577, in run
testMethod()
File "/home/roques/tools/django/django/test/testcases.py", line 1113, in
skip_wrapper
return test_func(*args, **kwargs)
File
"/home/roques/tools/django/tests/postgres_tests/test_aggregates.py", line
122, in test_json_agg
values =
AggregateTestModel.objects.aggregate(jsonagg=JsonAgg('char_field'))
File "/home/roques/tools/django/django/db/models/manager.py", line 85,
in manager_method
return getattr(self.get_queryset(), name)(*args, **kwargs)
File "/home/roques/tools/django/django/db/models/query.py", line 352, in
aggregate
return query.get_aggregation(self.db, kwargs.keys())
File "/home/roques/tools/django/django/db/models/sql/query.py", line
461, in get_aggregation
result = compiler.execute_sql(SINGLE)
File "/home/roques/tools/django/django/db/models/sql/compiler.py", line
829, in execute_sql
cursor.execute(sql, params)
File "/home/roques/tools/django/django/db/backends/utils.py", line 64,
in execute
return self.cursor.execute(sql, params)
File "/home/roques/tools/django/django/db/utils.py", line 94, in
__exit__
six.reraise(dj_exc_type, dj_exc_value, traceback)
File "/home/roques/tools/django/django/utils/six.py", line 685, in
reraise
raise value.with_traceback(tb)
File "/home/roques/tools/django/django/db/backends/utils.py", line 64,
in execute
return self.cursor.execute(sql, params)
django.db.utils.ProgrammingError: function jsonb_agg(character varying)
does not exist
LINE 1: SELECT JSONB_AGG("postgres_tests_aggregatetestmodel"."char_f...
^
HINT: No function matches the given name and argument types. You might
need to add explicit type casts.
}}}

--
Ticket URL: <https://code.djangoproject.com/ticket/27478>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.

[Django]

#27478: JSONB_AGG is not available in PostgreSQL 9.4
-------------------------------------+-------------------------------------

Reporter: Christian von | Owner: nobody

Roques |
Type: | Status: new
Cleanup/optimization |

Component: Uncategorized | Version: master
Severity: Normal | Resolution:

Keywords: JsonAgg JSONB_AGG | Triage Stage:

| Unreviewed
Has patch: 1 | Needs documentation: 0

Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------

Comment (by Mads Jensen):

Seems good. You may need to refer this ticket in the commit #26327.

--
Ticket URL: <https://code.djangoproject.com/ticket/27478#comment:1>

[Django]

#27478: JSONB_AGG is not available in PostgreSQL 9.4
-------------------------------------+-------------------------------------

Reporter: Christian von | Owner: nobody
Roques |

Type: | Status: closed
Cleanup/optimization |
Component: contrib.postgres | Version: master
Severity: Normal | Resolution: duplicate

Keywords: JsonAgg JSONB_AGG | Triage Stage:

| Unreviewed
Has patch: 1 | Needs documentation: 0

Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------

Changes (by Tim Graham):

* status: new => closed
* resolution: => duplicate
* component: Uncategorized => contrib.postgres

Comment:

Since the new feature isn't released, we can reopen the original ticket to
keep the discussion in one place. Thanks for the report.

--
Ticket URL: <https://code.djangoproject.com/ticket/27478#comment:2>