Create index on expression in migrations

[IgnisDa]

Motivation

I want to create a unique index which has an expression as a column.

create unique index on calendar_event (date, metadata_id, coalesce(metadata_extra_information, 'some-str'));

I tried this but it does not work.

        manager
            .create_index(
                Index::create()
                    .unique()
                    .name("calendar_event-date-metadataid-info__uq-idx")
                    .table(CalendarEvent::Table)
                    .col(CalendarEvent::Date)
                    .col(CalendarEvent::MetadataId)
                    .col(Expr::expr(Func::coalesce([
                        Expr::col(CalendarEvent::MetadataExtraInformation).into(),
                        Expr::val("some-str").into(),
                    ])))
                    .to_owned(),
            )
            .await?;

Proposed Solutions

An API to allow the above.

Current Workarounds

Manually executing the query.

[IgnisDa]

Hey @tyt2y3 is this possible yet using seaorm?

[traitmeta]

same too

[dipthegeezer]

Plus one on this from me too.