Sub-selects inside the in() operator

[giocondo]

Proposal:

It would be useful to have the ability to use sub-selects with the IN() operator so that it wouldn't be necessary to store the values in a temporary variable.

For example, something like this:

select * from `my_table` where in (`my_field`, (select `another_field` from `another_table` where `type` = 'typeA'));

Checklist:

^{To be completed by the assignee. Check off tasks that have been completed or are not applicable.}

• Implementation completed
• Tests developed
• Documentation updated
• Documentation reviewed
• OpenAPI YAML updated and issue created to rebuild clients

[sanikolaev]

Thanks for the feature request @giocondo