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CS411 Database Systems

CS411 Database Systems. Kazuhiro Minami. 13: Logging and Recovery. Outline. Transaction Atomicity Concurrency control Recovery Logging Redo Undo Redo/undo. Users and DB Programs. End users don't see the DB directly are only vaguely aware of its design

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Recovery

673 views • 47 slides

Recovery from Crashes

Recovery from Crashes. ACID. A transaction is atomic -- all or none property. If it executes partly, an invalid state is likely to result. A transaction, may change the DB from a consistent state to another consistent state. Otherwise it is rejected (aborted).

408 views • 31 slides

Transactions

Transactions. A process that reads or modifies the DB is called a transaction . It is a unit of execution of database operations. Basic JDBC transaction pattern Connection conn = ...; conn.setAutoCommit(false); try { ... //JDBC statements } finally { conn.commit(); }.

373 views • 25 slides

Transactions

Transactions. A process that reads or modifies the DB is called a transaction . It is a unit of execution of database operations. Basic JDBC transaction pattern Connection conn = ...; conn.setAutoCommit(false); try { ... //JDBC statements } finally { conn.commit(); }.

258 views • 25 slides

ICS 214A: Database Management Systems Fall 2002

ICS 214A: Database Management Systems Fall 2002. Lecture 18: Redo/Undo Logging and Media Failure Professor Chen Li. Motivation. Undo logging: cannot bring backup DB copies up to date Redo logging: need to keep all modified blocks in memory until commit Solution: undo/redo logging

324 views • 20 slides