Multi Step Processes hard
Why would you choose TCC (Try-Confirm-Cancel) over a Choreography-based Saga for a financial transfer?
- A TCC is faster.
- B Sagas cannot handle money.
- C TCC does not require a coordinator.
- D TCC allows you to 'Reserve' resources (Isolation) in the Try phase, ensuring the Confirm phase cannot fail due to insufficient funds, whereas Sagas might fail late.
Answer: D. TCC allows you to 'Reserve' resources (Isolation) in the Try phase, ensuring the Confirm phase cannot fail due to insufficient funds, whereas Sagas might fail late.
Sagas are reactive (do -> undo). TCC is proactive (reserve -> finalize). TCC solves the 'Dirty Read' problem by keeping the pending state invisible or locked until Confirmation.
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