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Dewitt Was Right

By Michael Stonebraker

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DWR

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Grids (cells, blades)

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Cheapest computing on the planet (coming)

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Shared nothing

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How does this relate to data bases?

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Go read about Gamma (circa 1985) M.I.T.

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But…….

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Buy the dreaded 2 phase commit

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Bad sandbox to play in M.I.T.

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Suppose

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Insist on replication of every table

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Done by SLAC, Walmart and most warehouses

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Disk space is cheap

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Replicas need not be organized the same way

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Process every update twice (independently)

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In general provide K-safety M.I.T.

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Crash Recovery

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Rebuild damaged object from a replica, not from a redo log

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Get rid of

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Redo (but not undo)

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Truncate undo log at EOT

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2 phase commit (prepare message) M.I.T.

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Net Result - No Mohan

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New sandbox:

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How to efficiently rebuild objects (especially partially damaged ones) from replicas M.I.T.