Lots of people thinks that Blockchain is a database, actually its not. Blockchain is a digital ledger where any transaction can be processed related to Finance, Medical, and any field which include value, these processed data are transparent, a platform once it is processed can't be reversed at any cost.
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https://bitcointalk.org/index.php?topic=2472787.0You're not the only one who think the same most of people in this forum are thinking the same way but let me remind them blockchain isn't a database.Once you put something inside on it you'll never able to re-write it.