Lot’s of people will be surprised (or shocked, when it happens in production) when they see that mysql can work like this:

Query:

SELECT transaction_id, amount FROM transactions WHERE amount>20.5

Response:

123|20.5

Query:

SELECT transaction_id, amount FROM transactions WHERE amount=20.5

Response:

No rows

So, 20.5 is really greater than 20.5 in sql database. Sometimes.

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