Thanks to Adam Johnson, Carlton Gibson, Mariusz Felisiak, and Raphael
Michel for mentoring this Google Summer of Code 2019 project and
everyone else who helped with the patch.
Special thanks to Mads Jensen, Nick Pope, and Simon Charette for
extensive reviews.
Co-authored-by: Mariusz Felisiak <felisiak.mariusz@gmail.com>
The sql_flush() positional argument sequences is replaced by the boolean
keyword-only argument reset_sequences. This ensures that the old
function signature can't be used by mistake when upgrading Django. When
the new argument is True, the sequences of the truncated tables will
reset. Using a single boolean value, rather than a list, allows making a
binary yes/no choice as to whether to reset all sequences rather than a
working on a completely different set.
Made deserialize_db_from_string() do not sort dependencies.
deserialize_db_from_string() doesn't use natural keys, so there is no
need to sort dependencies in serialize_db_to_string(). Moreover,
sorting models cause issues for circular dependencies.
Both backends order NULLs first on ascending ordering and last on
descending ordering which makes ORDER BY IS (NOT)? NULL wasteful when
asc(nulls_first) and desc(nulls_last) are used since it prevents indice
usage.
deserialize_db_from_string() loads the full serialized database
contents, which might contain forward references and cycles. That
caused IntegrityError because constraints were checked immediately.
Now, it loads data in a transaction with constraint checks deferred
until the end of the transaction.
The subtract_temporals() database operation was not handling expressions
returning SQL params in mixed database types.
Regression in 3543129822.
Thanks Reupen Shah for the report.
There was a special case in this property to return None when the
database backend supports time zone. However, only the PostgreSQL
backend supports time zones and it never uses this property.
MySQL & MariaDB support the standard IS NULL and IS NOT NULL so
the same workaround used for NULLS FIRST and NULLS LAST that is
used for SQLite < 3.30.0 can be used.
Thanks Simon Charette for the discussion.
This allows using expressions that have an output_field that is a
BooleanField to be used directly in a queryset filters, or in the
When() clauses of a Case() expression.
Thanks Josh Smeaton, Tim Graham, Simon Charette, Mariusz Felisiak, and
Adam Johnson for reviews.
Co-Authored-By: NyanKiyoshi <hello@vanille.bid>
This reduces duplication by allowing AutoField, BigAutoField and
SmallAutoField to inherit from IntegerField, BigIntegerField and
SmallIntegerField respectively. Doing so also allows for enabling the
max_length warning check and minimum/maximum value validation for auto
fields, as well as providing a mixin that can be used for other possible
future auto field types such as a theoretical UUIDAutoField.
Oracle requires the EXISTS expression to be wrapped in a CASE WHEN in
the following cases.
1. When part of a SELECT clause.
2. When part of a ORDER BY clause.
3. When compared against another expression in the WHERE clause.
This commit moves the systematic CASE WHEN wrapping of Exists.as_oracle
to contextual .select_format, Lookup.as_oracle, and OrderBy.as_oracle
methods in order to avoid unnecessary wrapping.
time.monotonic() available from Python 3.3:
- Nicely communicates a narrow intent of "get a local system monotonic
clock time" instead of possible "get a not necessarily accurate Unix
time stamp because it needs to be communicated to outside of this
process/machine" when time.time() is used.
- Its result isn't affected by the system clock updates.
There are two classes of time.time() uses changed to time.monotonic()
by this change:
- measuring time taken to run some code.
- setting and checking a "close_at" threshold for for persistent db
connections (django/db/backends/base/base.py).
Mariusz Felisiak
sage
Adam Johnson
Ian Foote
Hannes Ljungberg
David Wobrock
Jon Dufresne
Matthijs Kooijman
Tim Graham
Shipeng Feng
Simon Charette
shankarj67
aryan
Nick Pope
Aymeric Augustin
Caio Ariede
Johannes Hoppe
Adnan Umer
Vojtech Bocek
Matthew Schinckel
Nasir Hussain
Mads Jensen
Simon Charette
Hasan Ramezani
Min ho Kim
Andrew Godwin
Przemysław Suliga
Rob Golding-Day
Ville Skyttä
Paveł Tyślacki