New Feature Request: INSERT ON CONFLICT

[RockfordWei]

Proposal

Currently, the user has to determine if the database had already stored a duplicated key:

let table = db.table(ARecord.self)
if try table.where(\ARecord.id == record.id).count() > 0 {
   try table.update(record)
} else {
  try table.insert(record)
}

And apparently, the snippet above is low efficient and could not fully use the native SQL for INSERT ON CONFLICT.

The new upsert() or a general save() function should simplify the above code to:

try table.save(record)