SNOW-638840: Version 1.4.0 breaks SnowflakeDialect._get_schema_columns function when column of type DATE exists in schema

Please answer these questions before submitting your issue. Thanks!

1. What version of Python are you using?

Python 3.8.13 (default, Apr 18 2022, 15:19:59) 
[Clang 13.1.6 (clang-1316.0.21.2.3)]

1. What operating system and processor architecture are you using?

macOS-12.4-arm64-arm-64bit

1. What are the component versions in the environment (pip freeze)?

asn1crypto==1.5.1
certifi==2022.6.15
cffi==1.15.1
charset-normalizer==2.0.12
cryptography==36.0.2
idna==3.3
oscrypto==1.3.0
pycparser==2.21
pycryptodomex==3.15.0
PyJWT==2.4.0
pyOpenSSL==22.0.0
pytz==2022.1
requests==2.28.1
snowflake-connector-python==2.7.9
snowflake-sqlalchemy==1.4.0
SQLAlchemy==1.4.39
urllib3==1.26.10`

1. What did you do?

The following code will reproduce the issue when using a schema that has a column of type DATE:

from snowflake.sqlalchemy import URL
from sqlalchemy import create_engine, MetaData

engine = create_engine(URL(
    account = '####',
    user = '####',
    password = '####',
    database = '####',
    schema = '####',
    warehouse = '####',
    role='####',
    ))

meta = MetaData()
meta.reflect(bind=engine)

1. What did you expect to see?

The above code should execute successfully as it does with the previous version 1.3.4.

1. Can you set logging to DEBUG and collect the logs?

Error traceback:

/Users/enriquerodicio/Development/snowflake-python-test/venv/lib/python3.8/site-packages/snowflake/sqlalchemy/snowdialect.py:539: SAWarning: Did not recognize type 'DATE' of column 'applicationdate'
sa_util.warn(
Traceback (most recent call last):
File "test2.py", line 16, in <module>
 meta.reflect(bind=engine)
File "/Users/enriquerodicio/Development/snowflake-python-test/venv/lib/python3.8/site-packages/sqlalchemy/sql/schema.py", line 4887, in reflect
 Table(name, self, **reflect_opts)
File "<string>", line 2, in __new__
File "/Users/enriquerodicio/Development/snowflake-python-test/venv/lib/python3.8/site-packages/sqlalchemy/util/deprecations.py", line 309, in warned
 return fn(*args, **kwargs)
File "/Users/enriquerodicio/Development/snowflake-python-test/venv/lib/python3.8/site-packages/sqlalchemy/sql/schema.py", line 616, in __new__
 metadata._remove_table(name, schema)
File "/Users/enriquerodicio/Development/snowflake-python-test/venv/lib/python3.8/site-packages/sqlalchemy/util/langhelpers.py", line 70, in __exit__
 compat.raise_(
File "/Users/enriquerodicio/Development/snowflake-python-test/venv/lib/python3.8/site-packages/sqlalchemy/util/compat.py", line 208, in raise_
 raise exception
File "/Users/enriquerodicio/Development/snowflake-python-test/venv/lib/python3.8/site-packages/sqlalchemy/sql/schema.py", line 611, in __new__
 table._init(name, metadata, *args, **kw)
File "/Users/enriquerodicio/Development/snowflake-python-test/venv/lib/python3.8/site-packages/sqlalchemy/sql/schema.py", line 686, in _init
 self._autoload(
File "/Users/enriquerodicio/Development/snowflake-python-test/venv/lib/python3.8/site-packages/sqlalchemy/sql/schema.py", line 721, in _autoload
 conn_insp.reflect_table(
File "/Users/enriquerodicio/Development/snowflake-python-test/venv/lib/python3.8/site-packages/sqlalchemy/engine/reflection.py", line 774, in reflect_table
 for col_d in self.get_columns(
File "/Users/enriquerodicio/Development/snowflake-python-test/venv/lib/python3.8/site-packages/sqlalchemy/engine/reflection.py", line 497, in get_columns
 col_defs = self.dialect.get_columns(
File "/Users/enriquerodicio/Development/snowflake-python-test/venv/lib/python3.8/site-packages/snowflake/sqlalchemy/snowdialect.py", line 680, in get_columns
 schema_columns = self._get_schema_columns(connection, schema, **kw)
File "<string>", line 2, in _get_schema_columns
File "/Users/enriquerodicio/Development/snowflake-python-test/venv/lib/python3.8/site-packages/sqlalchemy/engine/reflection.py", line 55, in cache
 ret = fn(self, con, *args, **kw)
File "/Users/enriquerodicio/Development/snowflake-python-test/venv/lib/python3.8/site-packages/snowflake/sqlalchemy/snowdialect.py", line 555, in _get_schema_columns
 type_instance = col_type(**col_type_kw)
TypeError: 'NullType' object is not callable

[sfc-gh-aling]

hey guys, apologize for the issue here – as pointed out by @daniel-sali , it’s because of the DATE has been accidentally removed from the ischema_names map while the change isn’t detected by the tests.

sorry about causing you trouble and appreciate your help on identifying the issue, we will fix this and ship a new release.

[sfc-gh-aling]

thanks for your patience, we have released 1.4.1 which fixed the issue. please upgrade to the latest one and take a try. I’m closing the issue now, feel free to reach out if you’re still encountering the issue or see other issues.