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SQL Server Snapshot Isolation Level Problem

I am learning the SQL Server 2008 snapshot isolation level from the link below. My confusion

http://msdn.microsoft.com/en-us/library/ms173763.aspx

  • It is stated: "Data changes made by other transactions after the start of the current transaction are not visible to the operators executing in the current transaction." - it seems that the data transmitted by other transactions is not visible to the current transaction of the isolation level of the snapshot;

  • Mentioned: "A transaction running under the SNAPSHOT isolation level can view the changes made by this transaction." - It seems that the data transmitted by other transactions is visible to the current transaction of the isolation level of the snapshot.

It seems that 1 and 2 contradict each other? Any comments?

thanks in advance George

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2 answers

Number 2 means "I see my changes, I do not see other changes"

So, if I start a transaction and I make changes, I can see them. Other transactions for other sessions / connections started after my TXN was not able to see my changes.

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You also need to know the difference between SNAPSHOT and READ COMMITTED SNAPSHOT - for the latter you need to change your quote from BOL as follows:

" , ( !) , . "

, :

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Source: https://habr.com/ru/post/1712411/

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