Add Time Zone support on timestamp_column

[asyarif93]

Is your feature request related to a problem? Please describe.
In BigQuery A timestamp value represents an absolute point in time, independent of any time zone or convention such as daylight saving time (DST), with microsecond precision. Because of this, The Elementary complete "day" has partial data to what we actually have resulting to always giving anomaly.

Describe the solution you'd like
Allowing to add sql expression in timestamp_column. e.g.

meta:
  elementary:
    timestamp_column: "convert_timezone('UTC', 'Australia/Sydney', load_date)"

Describe alternatives you've considered
another options can be more user friendly by having

meta:
  elementary:
    timestamp_column: load_date
    convert_timestamp: 'Australia/Sydney'

but this might adding dependency as date conversion is vendor specific

Additional context
Also Related to https://elementary-community.slack.com/archives/C02CTC89LAX/p1683764020831119

Would you be willing to contribute this feature?
I haven't explore the source code, as i not sure this need to be raised in here or https://github.com/elementary-data/dbt-data-reliability

[haritamar]

Hi @asyarif93 !

Thanks for opening this issue and sorry for the delayed response.
I believe that actually a custom SQL should work for the timestamp column today (in the past we had validation that enforced it to be a column name and we removed it).
Does it not work for you?

Thanks,
Itamar