fix: add missing datetime64[ms] type mapping

[dacopan]

fix #44

[kenho811]

Hi @dacopan , and maintainers,

I am coming from the fork here

https://github.com/lenoyjacob/sqlalchemy_dremio

I raised the issue in dremio (see: https://community.dremio.com/t/superset-dremio-error-datetime64-ms-for-timestamp-field/11827)

I got the suggestion to try out that fork, and it solved my issue of the Superset connection to Dremio for timestamp date type (which is datetime64[ms])

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While this PR looks a bit different from the fork, I believe the main point is really just to add the mapping (https://github.com/narendrans/sqlalchemy_dremio/pull/45/files#diff-9deefcdbf269b1ac22873d58d61153c381ee4bb71719eff7f8404d0ebddcaf76R32)

For now, I am using the fork in my superset docker image.

Is there any chance that this PR could get merged?

Thank you

[chenym250]

Just to chime in, this issue appears for me when pandas version is ~2.0.3; downgrading pandas to 1.5.3 fixed the issue for me. FWIW, I agree that adding datetime64[ms] to the dict is the best approach here.

[cmdel]

I'd also like to see this merged if it solves this issue. I' tried the lennoyjacob fork but I'm getting a 'BadGateway' error instead.
Any chance you can add it to a milestone?
Thnx

[ohappykust]

Hi, @narendrans! Is there a chance this fix will make it into the master branch?