Nested Select Queries

[iSwiftter]

I have a tree like scheme where the items can have parent from the same table what I need is to query the items whose parent is deleted

select * from items as c where not exists (select p.id from items as p where c.parent_id == p.id)

I tried to achieve this as :

let child = ItemTable.table.alias("child")
let parent = ItemTable.table.alias("parent")
let parentExists = parent.filter(child[ItemTable.parentId] == parent[ItemTable.id]).exists
let r = child.filter(parentExists)

but the last line gives the following compilation error :

Cannot invoke 'filter' with an argument list of type '(Select<Bool>)'

I can write the whole code in sql and run the query, but I need to achieve this using the ORM provided by SQLite Swift.

[adamg89]

Any solution for this?