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- LATER review lab2
- LATER SQL join
- LATER Block 2
- LATER EER
- DONE EER
- Most useful additional concept of EER model:
specialization/generalization.
- Specialization
@ -1007,11 +1007,11 @@
- DONE Block 3
- DONE DB transaction management
- anomalies
- DONE ACID (Atomicity, Consistency, Isolation, Durability): A set of properties that guarantee the reliability and integrity of database transactions.
- 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.
- Consistency: The property that ensures a transaction transforms the database from one consistent state to another consistent state. It maintains data integrity and adheres to defined business rules.
- 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 ACID (Atomicity, Consistency, Isolation, Durability): A set of properties that guarantee the reliability and integrity of database transactions. #flashcard
- 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.
- Consistency: :-> The property that ensures a transaction transforms the database from one consistent state to another consistent state. It maintains data integrity and adheres to defined business rules.
- 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
- DONE Meaning of serialisability.
- DONE How locking can ensure serialisability.