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.
Text with more than 4000 characters must be set to as a CLOB on Oracle
what caused a mixed datatype error (ORA-01790) when shorter text
appeared in the same operation.
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.
The LIKE operator wildcard generated for contains, startswith, endswith and
their case-insensitive variant lookups was conflicting with parameter
interpolation on CREATE constraint statement execution.
Ideally we'd delegate parameters interpolation in DDL statements on backends
that support it but that would require backward incompatible changes to the
Index and Constraint SQL generating methods.
Thanks David Sanders for the report.
Removed DatabaseIntrospection.table_name_converter()/column_name_converter()
and use instead DatabaseIntrospection.identifier_converter().
Removed DatabaseFeatures.uppercases_column_names.
Thanks Tim Graham for the initial patch and review and Simon Charette
for the review.
Checked the following locations:
* Model.save(): If there are parents involved, take the safe way and use
transactions since this should be an all or nothing operation.
If the model has no parents:
* Signals are executed before and after the previous existing
transaction -- they were never been part of the transaction.
* if `force_insert` is set then only one query is executed -> atomic
by definition and no transaction needed.
* same applies to `force_update`.
* If a primary key is set and no `force_*` is set Django will try an
UPDATE and if that returns zero rows it tries an INSERT. The first
case is completly save (single query). In the second case a
transaction should not produce different results since the update
query is basically a no-op then (might miss something though).
* QuerySet.update(): no signals issued, single query -> no transaction
needed.
* Model/Collector.delete(): This one is fun due to the fact that is
does many things at once.
Most importantly though: It does send signals as part of the
transaction, so for maximum backwards compatibility we need to be
conservative.
To ensure maximum compatibility the transaction here is removed only
if the following holds true:
* A single instance is being deleted.
* There are no signal handlers attached to that instance.
* There are no deletions/updates to cascade.
* There are no parents which also need deletion.