Kendrick Lamar -- Receives Key to Compton ... Mayor Disses Drake

The sun was shining bright in LA Saturday, but it was decidedly shade in Compton as Mayor Aja Brown presented Kendrick Lamar with the keys to her city ... at Drake's expense.

The Mayor made it clear ... a key from Compton is way better than one from Toronto, which Drake received Friday.

She's not the first politician to favor Kendrick over Drake.