superset can not know the string/varchar columns from impala table

[zhouzach]

Make sure these boxes are checked before submitting your issue - thank you!

• [* ] I have checked the superset logs for python stacktraces and included it here as text if any
• [ *] I have reproduced the issue with at least the latest released version of superset
• [* ] I have checked the issue tracker for the same issue and I haven't found one similar

Superset version

0.18.4

Expected results

when Add Sqla Table, superset can get all right columns from impala table

Actual results

when Add Sqla Table, superset can not know the string/varchar columns from impala table

Steps to reproduce

1.have impala table:

2.Add Database from impala

3.Add Sqla Table
edit table->list table column, I find that the string/varchar columns can not be known by superset

[xrmx]

Sure this is an issue in superset and not in the sqlalchemy dialect / plumbing?

[zhouzach]

@xrmx I am a superset beginner, no idea about the problem.Do you use superset on impala table that has the string/varchar columns and succeed？

[xiaoyugit]

i had the same issue with 0.18.5

[jxb45]

Same issue. I'm on 0.18.5 as well. This maybe another issue, but Time Grains don't show for Impala as well.

[mistercrunch]

I wonder if the UNKOWN value comes out of the SQLAlchemy dialect or if it comes from us here:
https://github.com/apache/incubator-superset/blob/a141695b2b73df1d05d74c8ed8e22341e6e25edc/superset/connectors/sqla/models.py#L586

Do you see stack traces in your log when saving a Impala table? If so please paste it here. If not that means it's coming out as UNKNOWN out of the driver/dialect and needs to be fixed there.

[mistercrunch]

@JImBurris about time grains, they haven't been contributed yet for Impala. Someone needs to send a PR with a DBEngineSpec with time grains defined for impala, it's as simple as:
https://github.com/apache/incubator-superset/blob/master/superset/db_engine_specs.py#L193

[mistercrunch]

Here, can someone that has impala test this?
#3225

[mistercrunch]

Notice: this issue has been closed because it has been inactive for 264 days. Feel free to comment and request for this issue to be reopened.