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Ryan 2023-06-14 16:49:26 +08:00
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@ -1005,9 +1005,9 @@
- The instances of a potential subclass participate in a relationship unique to that subclass.
- DONE Block 3
- DONE DB transaction management
- NOW anomalies
- DONE anomalies
:LOGBOOK:
CLOCK: [2023-06-14 Wed 16:41:52]
CLOCK: [2023-06-14 Wed 16:41:52]--[2023-06-14 Wed 16:49:14] => 00:07:22
:END:
- DONE Deadlock and how it can be resolved. #flashcard
- A deadlock is a situation in which two or more transactions are unable
@ -1015,6 +1015,7 @@
resulting in a circular dependency and a system halt. It is a form of
resource contention that can occur in concurrent systems, including
database management systems.
- Cascading rollback #flashcard
- DONE ACID (Atomicity, Consistency, Isolation, Durability): A set of properties that guarantee the reliability and integrity of database transactions. #flashcard
collapsed:: true
- Atomicity: :-> The property that ensures a transaction is treated as a single, indivisible unit of work. It either executes all its operations successfully or rolls back to the initial state if any operation fails.
@ -1022,7 +1023,7 @@
- Isolation: :-> The property that ensures concurrent transactions do not interfere with each other. Each transaction operates in isolation until it completes, preventing interference or conflicts.
- Durability: :-> The property that ensures committed changes made by a transaction are permanently saved and will survive any subsequent system failures or crashes.
- DONE Concurrency control
- LATER Meaning of serialisability.
- DONE Meaning of serialisability. #flashcard
- The objective of serialisability is to find nonserial schedules that are equivalent to some serial schedule. Such a schedule is called serialisable.
- DONE How locking can ensure serialisability. #flashcard
- Locking achieves serializability by using locks to control access to