Commit 95eb68c9 authored by Tim Graham's avatar Tim Graham
Browse files

Fixed #17339 -- Factor out has_result into database backend. 

Thanks jonash.
parent c0a4894d

django/db/models/sql/compiler.py

+10 −0
Original line number Diff line number Diff line
@@ -750,6 +750,16 @@ class SQLCompiler(object): 


                yield row



    def has_results(self):

        """

        Backends (e.g. NoSQL) can override this in order to use optimized

        versions of "query has any results."

        """

        # This is always executed on a query clone, so we can modify self.query

        self.query.add_extra({'a': 1}, None, None, None, None, None)

        self.query.set_extra_mask(['a'])

        return bool(self.execute_sql(SINGLE))



    def execute_sql(self, result_type=MULTI):

        """

        Run the query against the database and returns the result(s). The

django/db/models/sql/query.py

+1 −3
Original line number Diff line number Diff line
@@ -401,12 +401,10 @@ class Query(object): 
    def has_results(self, using):

        q = self.clone()

        q.clear_select_clause()

        q.add_extra({'a': 1}, None, None, None, None, None)

        q.set_extra_mask(['a'])

        q.clear_ordering(True)

        q.set_limits(high=1)

        compiler = q.get_compiler(using=using)

        return bool(compiler.execute_sql(SINGLE))

        return compiler.has_results()



    def combine(self, rhs, connector):

        """