Upsert with autoincrement

[AUsachov]

Let's say that we have tables:
parent {
id: autincrement
stuff: int },

child {
id: autoincrement,
parent_id,
data: int}

I want to upsert this tables. Upsert command for child will looks like
new UpsertChildCommand(uniqueKey(childEntity.data).identifier(some_data)) BUT unique key in child should be the combination parent_id and data. How i can handle it?

[effiban]

@AUsachov - can you please ask this on StackOverflow instead?