Seemingly unnecessary error on type unions

[jollygreenlaser]

• EdgeDB Version: EdgeDB Version: 4.4+596d0e4 on Ubuntu 22.04.3 LTS
• EdgeDB CLI Version: EdgeDB CLI 4.1.0+a8fe4d7

SchemaError: it is illegal to create a type union that causes a computed property 'fee' to mix with other versions of the same property 'fee'

Coming from:

with
event := (select Event filter .id = <uuid>$0)
patrons := {
  (select (insert Patron {
    user := (select User filter .username = 'Alice'),
    event := event,
  }) {
    fee := event.fee,
  }),
  (select (insert Patron {
    user := (select User filter .username = 'Bob'),
    event := event,
  }) {
    fee := event.fee,
  }),
}
select {
  event := event,
  patrons := patrons,
  total := sum(patrons.fee),
  ...
}

This query is being string built because when it was JSON input it took forever to run and now the string built version is actually performant. So the select (insert Patron...) { fee } part used to be a for over JSON.

It worked fine when it was JSON. Now I get that error. Despite fee being float32 - unclear why it doesn't like the type?

I'm working to refactor the query to hopefully fix this but unclear why it's even an issue.

[msullivan]

We don't support doing unions of types with computed properties. Eventually we'll fix this, but it's tricky for a few reasons.

Try putting the shape on the outside of the union?

[jollygreenlaser]

In this case, my refactor was to remove the computed property and change the final select to total := sum((select patrons { fee := .event.fee }).fee). The tricky part here of course being that patrons.event.fee won't work because the events ends up as an intermediate set that is implicitly distinct. Which I believe was what I was trying to dodge back when I originally wrote this.

Thanks for the help. I could see supporting this being mildly useful but not nearly important enough if there's tricky stuff under the hood.