diff options
Diffstat (limited to 'django/db/models/sql')
| -rw-r--r-- | django/db/models/sql/compiler.py | 10 | ||||
| -rw-r--r-- | django/db/models/sql/query.py | 4 |
2 files changed, 11 insertions, 3 deletions
diff --git a/django/db/models/sql/compiler.py b/django/db/models/sql/compiler.py index 0b12bd1552..e17cb3f616 100644 --- a/django/db/models/sql/compiler.py +++ b/django/db/models/sql/compiler.py @@ -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 diff --git a/django/db/models/sql/query.py b/django/db/models/sql/query.py index 110925114c..2a9b8ef826 100644 --- a/django/db/models/sql/query.py +++ b/django/db/models/sql/query.py @@ -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): """ |