diff options
Diffstat (limited to 'django/db/models')
| -rw-r--r-- | django/db/models/expressions.py | 29 |
1 files changed, 9 insertions, 20 deletions
diff --git a/django/db/models/expressions.py b/django/db/models/expressions.py index 44a52c1dc9..13e0ef172c 100644 --- a/django/db/models/expressions.py +++ b/django/db/models/expressions.py @@ -1128,11 +1128,17 @@ class OrderBy(BaseExpression): return [self.expression] def as_sql(self, compiler, connection, template=None, **extra_context): - if not template: + template = template or self.template + if connection.features.supports_order_by_nulls_modifier: + if self.nulls_last: + template = '%s NULLS LAST' % template + elif self.nulls_first: + template = '%s NULLS FIRST' % template + else: if self.nulls_last: - template = '%s NULLS LAST' % self.template + template = '%%(expression)s IS NULL, %s' % template elif self.nulls_first: - template = '%s NULLS FIRST' % self.template + template = '%%(expression)s IS NOT NULL, %s' % template connection.ops.check_expression_support(self) expression_sql, params = compiler.compile(self.expression) placeholders = { @@ -1144,23 +1150,6 @@ class OrderBy(BaseExpression): params *= template.count('%(expression)s') return (template % placeholders).rstrip(), params - def as_sqlite(self, compiler, connection): - template = None - if connection.Database.sqlite_version_info < (3, 30, 0): - if self.nulls_last: - template = '%(expression)s IS NULL, %(expression)s %(ordering)s' - elif self.nulls_first: - template = '%(expression)s IS NOT NULL, %(expression)s %(ordering)s' - return self.as_sql(compiler, connection, template=template) - - def as_mysql(self, compiler, connection): - template = None - if self.nulls_last: - template = 'ISNULL(%(expression)s), %(expression)s %(ordering)s ' - elif self.nulls_first: - template = 'IF(ISNULL(%(expression)s),0,1), %(expression)s %(ordering)s ' - return self.as_sql(compiler, connection, template=template) - def as_oracle(self, compiler, connection): # Oracle doesn't allow ORDER BY EXISTS() unless it's wrapped in # a CASE WHEN. |