How hard is it to change the uid key to be a larger value

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2

I had a similar-ish situation here: Referencing foreign UIDs in dgraph - #2 by janardhan

One thought is you can just store the source system ID in a string predicate. So you would run a mutation like this when you’re loading your foreign entities into Dgraph:

mutation {
 set {
  _:sourceEntity1 <ForeignUID> "[string representation of source 256-bit UID]" .
  _:sourceEntity2 <ForeignUID> "[string representation of source 256-bit UID]" .
  ....
 }
}

Then to index the ForeignUID predicate and make it searchable with the full foriegn UID, you would add ForeignUID to the Dgraph schema with:

mutation {
  schema {
    ForeignUID: string @index(exact) .
  }
}