The Slippery Concept of a Transaction

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The Meaning of ACID

Single-Object and Multi-Object Operations

Weak Isolation Levels

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Read Committed

Snapshot Isolation and Repeatable Read

Preventing Losg Updates

Write Skew and Pantoms

Serializability

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Actual Serial Execution

Two-Phase Locking (2PL)

Serializable Snapshot Isolation (SSI)