2
votes
Accepted
Does basic 2 PL always ensure conflict serializability?
No,
If you use 2PL protocol you are guaranteed to have a conflict-serializable schedule but there are conflict serializable schedules which may not honour 2 PL protocol i.e. locking data items in the ...
- 36
2
votes
Why do OS and DBMS have their own synchronisation mechanisms, when OS can alone do it and it sits at the bottom of DB?
Program synchronization is a very different beast compared to transaction synchronization. The objective of your Operating System is to have multiple applications working in sync to maximize the ...
- 884
1
vote
Accepted
How are blind writes recoverable in a transaction schedule?
T1 T2
R(A)
W(A)
W(A)
Commit
Commit
is not recoverable, even though it satisfies the condition you mentioned about the commit order of ...
- 186
1
vote
Accepted
What will you do if multiple users access your application at the same time?
my answer to the first problem would go like this:
From a logical perspective, it depends on the actual purpose of the application, however, we should at least ensure safety and liveness, therefore ...
- 463
1
vote
how two phase commit ensure serializability
For how to ensure serializable.
The atomic commit protocol like 2PC only ensures the "atomicity" property, i.e. a cross-shard transaction either commits or aborts on all participants.
The &...
- 11
1
vote
how two phase commit ensure serializability
Let me try to explain this using an example. Suppose there is coordinator and two participants named P1 & ...
- 111
Only top scored, non community-wiki answers of a minimum length are eligible