I read that corrected isolation can provide significantly more concurrency than a serializable isolation level.
My question is here. How does read isolation provide more concurrency than serializable? . A short script will be a big help
Question: Say the two transactions tran1 and tran2 begin (when I say that the transaction begins, here does this mean that the transaction starts when they start some query Right? ) At time t1. If tran1 updates row1 at time t2 and later at time t3 tran2 selects the same row, it will not receive the updated row made by tran1. Right? I said this because tran1 and tran2 will represent the result from the data state that was present at time t1. Right? Does the transaction take a snapshot of the complete database when it starts?
I read that encoding serializable transactions requires additional work by the application developer to check the error "Unable to serialize access" and cancel and repeat the transaction. Not sure when the developer will receive the message "Can not serialize access"? We will get the same error in the scenario below
Say two transactions tran1 and tran2 at time t1. If tran1 updates row1 and commits at time t2 and later at time t3, tran2 updates and commits the same row1. Will he throw a "Can not serialize access" error in this case? If yes, Opernik supports the internal version of the version in the case of serializable transactions, to find out that the row has been updated by the user?
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