SNOW-629067 connector executemany handle escaping double percents when no params (#315)

Author: sfc-gh-aling

src/snowflake/sqlalchemy/base.py

@@ -400,6 +400,8 @@ def render_literal_value(self, value, type_):
 
 
 class SnowflakeExecutionContext(default.DefaultExecutionContext):
+    INSERT_SQL_RE = re.compile(r"^insert\s+into", flags=re.IGNORECASE)
+
     def fire_sequence(self, seq, type_):
         return self._execute_scalar(
             f"SELECT {self.identifier_preparer.format_sequence(seq)}.nextval",
@@ -425,7 +427,7 @@ def should_autocommit(self):
             return autocommit and not self.isddl
 
     def pre_exec(self):
-        if self.compiled:
+        if self.compiled and self.identifier_preparer._double_percents:
             # for compiled statements, percent is doubled for escape, we turn on _interpolate_empty_sequences
             if hasattr(self._dbapi_connection, "driver_connection"):
                 # _dbapi_connection is a _ConnectionFairy which proxies raw SnowflakeConnection
@@ -436,8 +438,15 @@ def pre_exec(self):
                 # _dbapi_connection is a raw SnowflakeConnection
                 self._dbapi_connection._interpolate_empty_sequences = True
 
+            # if the statement is executemany insert, setting _interpolate_empty_sequences to True is not enough,
+            # because executemany pre-processes the param binding and then pass None params to execute so
+            # _interpolate_empty_sequences condition not getting met for the command.
+            # Therefore, we manually revert the escape percent in the command here
+            if self.executemany and self.INSERT_SQL_RE.match(self.statement):
+                self.statement = self.statement.replace("%%", "%")
+
     def post_exec(self):
-        if self.compiled:
+        if self.compiled and self.identifier_preparer._double_percents:
             # for compiled statements, percent is doubled for escapeafter execution
             # we reset _interpolate_empty_sequences to false which is turned on in pre_exec
             if hasattr(self._dbapi_connection, "driver_connection"):

tests/sqlalchemy_test_suite/test_suite.py

@@ -11,7 +11,6 @@
 from sqlalchemy.testing.suite import InsertBehaviorTest as _InsertBehaviorTest
 from sqlalchemy.testing.suite import LikeFunctionsTest as _LikeFunctionsTest
 from sqlalchemy.testing.suite import LongNameBlowoutTest as _LongNameBlowoutTest
-from sqlalchemy.testing.suite import PercentSchemaNamesTest as _PercentSchemaNamesTest
 from sqlalchemy.testing.suite import SimpleUpdateDeleteTest as _SimpleUpdateDeleteTest
 from sqlalchemy.testing.suite import *  # noqa
 
@@ -68,18 +67,7 @@ def test_empty_insert_multiple(self, connection):
         pass
 
 
-# 3. Need fix in connector
-
-
-class PercentSchemaNamesTest(_PercentSchemaNamesTest):
-    @pytest.mark.xfail
-    # TODO: connector cursor "executemany" needs to handle double percentage like
-    #  "execute" using self._dbapi_connection._interpolate_empty_sequences
-    def test_executemany_roundtrip(self, connection):
-        super().test_executemany_roundtrip(connection)
-
-
-# 4. Patched Tests
+# 2. Patched Tests
 
 
 class HasSequenceTest(_HasSequenceTest):