Its not, its still read committed. Its the same thing as if you had to read from two rows in a transaction, and your isolation was read committed, and both thos

Its not, its still read committed. Its the same thing as if you had to read from two rows in a transaction, and your isolation was read committed, and both those rows would be modified by a different transaction. Its possible you read the first row, a transaction is committed and then you read the second row with the updates from the transaction. You have just read a partial commit. It is ACID and it is not serializable, the thing is MySQL lets you use higher levels of isolation like repeatable read or serializable which are very useful and today Vitess can't guarantee that in a 2PC.