23 lines
988 B
Markdown
23 lines
988 B
Markdown
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# Snapshots
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A "snapshot" is a record of the current database state stored in permanent
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storage. Note that the term "snapshot" is used also in the context of
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the transaction engine to denote a set of running transactions.
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A snapshot is written to the file by Memgraph periodically if so
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configured. The snapshot creation process is done within a transaction created
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specifically for that purpose. The transaction is needed to ensure that
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the stored state is internally consistent.
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The database state can be recovered from the snapshot during startup, if
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so configured. This recovery works in conjunction with write-ahead log
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recovery.
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A single snapshot contains all the data needed to recover a database. In
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that sense snapshots are independent of each other and old snapshots can
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be deleted once the new ones are safely stored, if it is not necessary
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to revert the database to some older state.
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The exact format of the snapshot file is defined inline in the snapshot
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creation code.
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