Abstract
SNAPSHOT isolation provides a protocol for dealing with concurrent transactions in transaction processing applications. Because applications using SNAPSHOT isolation can have very high throughput, many applications are designed using this protocol.
However, SNAPSHOT isolation can produce non-serializable and incorrect schedules. One interesting question is: why are there not more complaints from users that they are getting incorrect results when they use SNAPSHOT isolation?
The most likely answer to that question is that application designers use some design pattern that produces correct schedules at SNAPSHOT isolation. The designers are not necessarily selecting a design pattern because it will guarantee correctness at SNAPSHOT isolation. They are just using design patterns that seem natural to them, and those patterns happen to produce correct executions at SNAPSHOT isolation.
This paper reviews some previous work on sufficient conditions for correctness at SNAPSHOT isolation and then presents an example of a design pattern that is guaranteed to produce correct schedules at SNAPSHOT isolation.
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Lewis, P. (2009). SNAPSHOT Isolation: Why Do Some People Call it SERIALIZABLE?. In: Ravi, S.S., Shukla, S.K. (eds) Fundamental Problems in Computing. Springer, Dordrecht. https://doi.org/10.1007/978-1-4020-9688-4_13
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DOI: https://doi.org/10.1007/978-1-4020-9688-4_13
Publisher Name: Springer, Dordrecht
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