Merge pull request datajoint#854 from dimitri-yatsenko/cascade-delete

fix datajoint#853 -- queries with `is null` and `is not null` work correctly

Author: guzman-raphael

LNX-docker-compose.yml

@@ -32,7 +32,7 @@ services:
       interval: 1s
   fakeservices.datajoint.io:
     <<: *net
-    image: raphaelguzman/nginx:v0.0.10
+    image: raphaelguzman/nginx:v0.0.13
     environment:
     - ADD_db_TYPE=DATABASE
     - ADD_db_ENDPOINT=db:3306

datajoint/condition.py

@@ -202,5 +202,5 @@ def extract_column_names(sql_expression):
     s = re.sub(r"(\b[a-z][a-z_0-9]*)\(", "(", s)
     remaining_tokens = set(re.findall(r"\b[a-z][a-z_0-9]*\b", s))
     # update result removing reserved words
-    result.update(remaining_tokens - {"in", "between", "like", "and", "or"})
+    result.update(remaining_tokens - {"is", "in", "between", "like", "and", "or", "null", "not"})
     return result

local-docker-compose.yml

@@ -34,7 +34,7 @@ services:
       interval: 1s
   fakeservices.datajoint.io:
     <<: *net
-    image: raphaelguzman/nginx:v0.0.10
+    image: raphaelguzman/nginx:v0.0.13
     environment:
     - ADD_db_TYPE=DATABASE
     - ADD_db_ENDPOINT=db:3306

tests/schema.py

@@ -146,7 +146,7 @@ def make(self, key):
         populate with random data
         """
         from datetime import date, timedelta
-        users = User().fetch()['username']
+        users = [None, None] + list(User().fetch()['username'])
         random.seed('Amazing Seed')
         self.insert(
             dict(key,
@@ -155,7 +155,6 @@ def make(self, key):
                  username=random.choice(users))
             for experiment_id in range(self.fake_experiments_per_subject))
 
-
 @schema
 class Trial(dj.Imported):
     definition = """   # a trial within an experiment

tests/test_relational_operand.py

@@ -290,6 +290,15 @@ def test_pandas_fetch_and_restriction():
         assert_true(isinstance(df, pandas.DataFrame))
         assert_equal(len(E & q), len(E & df))
 
+    @staticmethod
+    def test_restriction_by_null():
+        assert_true(len(Experiment & 'username is null') > 0)
+        assert_true(len(Experiment & 'username is not null') > 0)
+
+    @staticmethod
+    def test_restriction_between():   # see issue
+        assert_true(len(Experiment & 'username between "S" and "Z"') < len(Experiment()))
+
     @staticmethod
     def test_restrictions_by_lists():
         x = D()