fix: Time Offset in SQLite and refine logic in Date Type conversion

[zhaoyongjie]

SUMMARY

Currently, The Time Offset can't be used in SQLite as datasouce, it's because the Pandas + SQLAlchemy query from SQLite will return datetime column as object rather than datetime.

... from sqlalchemy import create_engine
... import pandas as pd

... sqlite_engine = create_engine("sqlite:////some-path/examples_sqlite.db")
... sql_sqlite = '''
SELECT * FROM main.birth_names_sqlite
limit 1
'''
... df = pd.read_sql(sql_sqlite, sqlite_engine)
... df.dtypes
...
ds        object
gender    object
name      object
num        int64
state     object
dtype: object

This PR uses the original normalize_dttm_col function but adds a new argument for it. the normalize_dttm_col will convert the old __timestamp column or the new BASE_AXIS to the Timestamp series in pandas.

In addition, added a new unit test for Time Grain and Time Offset in the QueryObject.

BEFORE/AFTER SCREENSHOTS OR ANIMATED GIF

After

FF Enabled

FF Disabled

Before

FF Enabled

TESTING INSTRUCTIONS

ADDITIONAL INFORMATION

• Has associated issue:
• Required feature flags:
• Changes UI
• Includes DB Migration (follow approval process in SIP-59)
  • Migration is atomic, supports rollback & is backwards-compatible
  • Confirm DB migration upgrade and downgrade tested
  • Runtime estimates and downtime expectations provided
• Introduces new feature or API
• Removes existing feature or API

[codecov]

Codecov Report

Merging #21378 (4387f29) into master (1c0bff3) will increase coverage by 0.01%.
The diff coverage is 93.47%.

@@            Coverage Diff             @@
##           master   #21378      +/-   ##
==========================================
+ Coverage   66.67%   66.68%   +0.01%     
==========================================
  Files        1791     1791              
  Lines       68458    68476      +18     
  Branches     7270     7270              
==========================================
+ Hits        45642    45661      +19     
+ Misses      20955    20954       -1     
  Partials     1861     1861              

Flag	Coverage Δ
hive	53.08% <71.73%> (+0.04%)	⬆️
mysql	78.20% <91.30%> (+0.01%)	⬆️
postgres	78.27% <91.30%> (+0.01%)	⬆️
presto	52.98% <71.73%> (+0.04%)	⬆️
python	81.41% <93.47%> (+0.01%)	⬆️
sqlite	76.76% <91.30%> (+0.01%)	⬆️
unit	51.05% <36.95%> (+0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
superset/viz.py	58.17% <ø> (ø)
superset/common/query_context_processor.py	88.51% <90.90%> (-0.29%)	⬇️
superset/utils/core.py	90.32% <94.28%> (+0.38%)	⬆️

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more

[villebro]

Left a few comments

[villebro]

Tested to work as expected. I left one last comment that I'd be curious to hear your thoughts on, but this is probably already ok for merging to unblock the fix which is more serious than the remaining comment.

[villebro]

LGTM, thanks for all the iterations on this one!