Commit 1cdfbde4 authored by Josh Smeaton's avatar Josh Smeaton
Browse files

Fixed #23753 -- Oracle failure with Coalesce

parent 932d449f

django/db/models/functions.py

+12 −0
Original line number Diff line number Diff line
@@ -16,6 +16,18 @@ class Coalesce(Func): 
            raise ValueError('Coalesce must take at least two expressions')

        super(Coalesce, self).__init__(*expressions, **extra)



    def as_oracle(self, compiler, connection):

        # we can't mix TextField (NCLOB) and CharField (NVARCHAR), so convert

        # all fields to NCLOB when we expect NCLOB

        if self.output_field.get_internal_type() == 'TextField':

            class ToNCLOB(Func):

                function = 'TO_NCLOB'



            expressions = [

                ToNCLOB(expression) for expression in self.get_source_expressions()]

            self.set_source_expressions(expressions)

        return super(Coalesce, self).as_sql(compiler, connection)





class ConcatPair(Func):

    """

tests/db_functions/tests.py

+12 −0
Original line number Diff line number Diff line
@@ -56,6 +56,18 @@ class FunctionTests(TestCase): 
            lambda a: a.headline

        )



        # mixed Text and Char wrapped

        article = Article.objects.annotate(

            headline=Coalesce(Lower('summary'), Lower('text'), output_field=TextField()),

        )



        self.assertQuerysetEqual(

            article.order_by('title'), [

                lorem_ipsum.lower(),

            ],

            lambda a: a.headline

        )



    def test_concat(self):

        Author.objects.create(name='Jayden')

        Author.objects.create(name='John Smith', alias='smithj', goes_by='John')