1. Transaction
1.1. Recovery
1.1.1. Log based Recovery
1.1.1.1. Deferred modification technique
1.1.1.2. Immediate modification technique
1.2. ACID property
1.2.1. Atomicity
1.2.2. Consistency
1.2.3. Isolation
1.2.4. Durability
2. Concurrency Control
2.1. Serializability
2.1.1. Serializable Schedule
2.1.1.1. Conflict Serializable
2.1.1.2. View Serializable
2.1.2. Non-Serializable
2.2. Concurrency Control Techniques
2.2.1. Lock Based Protocol
2.2.1.1. Basic 2-phase locking Protocol
2.2.1.1.1. 2 Phase
2.2.1.1.2. Advantages
2.2.1.1.3. Lock starting of transactions with same variable
2.2.1.2. Strict 2-PL protocol
2.2.1.2.1. Exclusive Lock Unlock only after Transaction Commit
2.2.1.2.2. Recoverable
2.2.1.2.3. Deadlock Possible
2.2.1.3. Rigorous 2-PL Protocol
2.2.1.3.1. Exclusive/Shared Lock, Unlock tabhi honge jb Transaction Commit ho jae
2.2.1.3.2. Recoverable
2.2.1.3.3. Deadlock Possible
2.2.1.4. Conservative 2-PL Protocol
2.2.1.4.1. Trans. will start only when jb usko sare lock mil jaenge
2.2.1.4.2. Serializable
2.2.1.4.3. No Deadlock
2.2.1.5. Lock Upgradation / Downgradation
2.2.1.5.1. Upgradation
2.2.1.5.2. Downgradation
2.2.1.5.3. Advantages
2.2.2. Tree Protocol
2.2.2.1. Advantages
2.2.2.1.1. ensure Conflict Serializable
2.2.2.1.2. Deadlock Free
2.2.2.1.3. Unlock anyTime
2.2.2.1.4. More Concurrency than 2-Phase Locking
2.2.2.2. Disadvantages
2.2.2.2.1. Cascading Rollback
2.2.2.3. Can't be Cyclic
2.2.3. Time-Stamp Protocol
2.2.3.1. 2-Data item
2.2.3.1.1. R-timestamp(X)
2.2.3.1.2. W-timestamp(X)
2.2.3.2. Issues
2.2.3.2.1. Ti issue Read(X)
2.2.3.2.2. Ti issue Write(X)
2.2.3.3. Advantages
2.2.3.3.1. ensure Serializable
2.2.3.3.2. Free from Deadlock
2.2.3.4. DiaAdvantage
2.2.3.4.1. Starvation
2.2.3.5. THOMAS Write Rule
2.2.3.5.1. Ignore outdated writes