Front-end doesn't guess data types

[susodapop]

Issue Summary

After reading through #3553 I expected the front-end to accurately parse an ISO8601 date from a text-field. But it doesn't. If I select a bunch of ISO8601 dates as text fields from the database, Redash should let me reformat them using format codes.

Steps to Reproduce

I created an example on the redash demo instance here. You can reproduce on your own in Postgres with a query like this:

SELECT CAST(any_date_field as VARCHAR(50)) FROM table_of_your_choice

If you try to edit the table visualization to render a date field as MMM-YYYY or something similar it will not work.

Technical details:

• Redash Version: 7.0.0
• Browser/OS: Safari, Chrome, Firefox
• How did you install Redash: SaaS

[kravets-levko]

@susodapop Can you please provide data sample? Redash does guess date/time types, but it expects two formats (d is for any digit): string that starts with pattern dddd-dd-ddT - for date/time, and string that matches pattern dddd-dd-dd - for date. CAST will convert date/time filed to a bit different format: 2019-01-25 15:40:47+00 - notice that T is missing there. If you'll change your SQL to something like

SELECT REPLACE(CAST(any_date_field AS VARCHAR(50)), ' ', 'T')
FROM table_of_your_choice

it will work fine.

[susodapop]

Thanks @kravets-levko! Closing this issue as resolved.