The author poses the question in the book: “Do we even need transactions?”.But there is no technical reason distributed transactions are not possible.This can also cause problems for high performance or availability needs.Many distributed databases / datastores don’t have transactions because they are difficult to implement across partitions.Transactions are more typically known for grouping multiple object writes into a single operational unit.These types of operations are useful for ensuring good writes when multiple clients are attempting to write the same object concurrently.Another operation used is a compare and set.Some databases use a more complex atomic setup, such as an incrementer, eliminating the need for a read, modify, write cycle.Isolation is achieved by locking the object to be written.Atomicity is achievable with a log for crash recovery.It’s for this reason that nearly all databases must support single object atomicity and isolation.
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