If a user is configuring a custom SQL test, we could present them the results

[dividor]

Is your feature request related to a problem? Please describe.
Would be nice to display custom SQL results to the user if possible, with a LIMIT 10 at the end as well as confirmation their SQL is valid.

Describe the solution you'd like
When configuring custom sql test, run the sql with LIMIT 10, then either display results or SQL error message. Note, might be challenging for nested sub-queries.

Additional context
If we can get a preview it would allow us to provide a pick list of field for the user to set id field.