I was prowling StackOverflow today and the question was asked when you would use 2 databases. I’m amazed at the number of answers of replication and sharding (some under the guise of some other description). The only answer I can think of to be correct is Different Applications/Services (shared hosting probably falls under those 2 in a weird way). I’m going to explain why a replicated database and/or a sharded database are not multiple databases.
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