45 lines
1.7 KiB
Go
45 lines
1.7 KiB
Go
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/*
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Package bolt implements a low-level key/value store in pure Go. It supports
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fully serializable transactions, ACID semantics, and lock-free MVCC with
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multiple readers and a single writer. Bolt can be used for projects that
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want a simple data store without the need to add large dependencies such as
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Postgres or MySQL.
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Bolt is a single-level, zero-copy, B+tree data store. This means that Bolt is
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optimized for fast read access and does not require recovery in the event of a
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system crash. Transactions which have not finished committing will simply be
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rolled back in the event of a crash.
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The design of Bolt is based on Howard Chu's LMDB database project.
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Bolt currently works on Windows, Mac OS X, and Linux.
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Basics
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There are only a few types in Bolt: DB, Bucket, Tx, and Cursor. The DB is
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a collection of buckets and is represented by a single file on disk. A bucket is
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a collection of unique keys that are associated with values.
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Transactions provide either read-only or read-write access to the database.
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Read-only transactions can retrieve key/value pairs and can use Cursors to
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iterate over the dataset sequentially. Read-write transactions can create and
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delete buckets and can insert and remove keys. Only one read-write transaction
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is allowed at a time.
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Caveats
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The database uses a read-only, memory-mapped data file to ensure that
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applications cannot corrupt the database, however, this means that keys and
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values returned from Bolt cannot be changed. Writing to a read-only byte slice
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will cause Go to panic.
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Keys and values retrieved from the database are only valid for the life of
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the transaction. When used outside the transaction, these byte slices can
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point to different data or can point to invalid memory which will cause a panic.
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*/
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package bolt
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