Fixed #31248 -- Added missing space before USING SQL on PostGIS.

django/contrib/gis/db/backends/postgis/schema.py

@@ -37,7 +37,7 @@ class PostGISSchemaEditor(DatabaseSchemaEditor):
             self.sql_create_index,
             name=self.quote_name('%s_%s_id' % (model._meta.db_table, field.column)),
             table=self.quote_name(model._meta.db_table),
-            using='USING %s' % self.geom_index_type,
+            using=' USING %s' % self.geom_index_type,
             columns=field_column,
             extra='',
             condition='',

tests/gis_tests/geoapp/test_indexes.py

@@ -0,0 +1,19 @@
+from unittest import skipUnless
+
+from django.db import connection
+from django.db.models import Index
+from django.test import TestCase
+
+from ..utils import postgis
+from .models import City
+
+
+class SchemaIndexesTests(TestCase):
+    @skipUnless(postgis, 'This is a PostGIS-specific test.')
+    def test_using_sql(self):
+        index = Index(fields=['point'])
+        editor = connection.schema_editor()
+        self.assertIn(
+            '%s USING ' % editor.quote_name(City._meta.db_table),
+            str(index.create_sql(City, editor)),
+        )