24 lines
1.2 KiB
Text
24 lines
1.2 KiB
Text
cdb is a fast, reliable, lightweight package for creating and reading
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constant databases. Its database structure provides several features:
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* Fast lookups: A successful lookup in a large database normally takes
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just two disk accesses. An unsuccessful lookup takes only one.
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* Low overhead: A database uses 2048 bytes, plus 24 bytes per record,
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plus the space for keys and data.
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* No random limits: cdb can handle any database up to 4 gigabytes. There
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are no other restrictions; records don't even have to fit into memory.
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Databases are stored in a machine-independent format.
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* Fast atomic database replacement: cdbmake can rewrite an entire
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database two orders of magnitude faster than other hashing packages.
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* Fast database dumps: cdbdump prints the contents of a database in
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cdbmake-compatible format.
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cdb is designed to be used in mission-critical applications like e-mail.
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Database replacement is safe against system crashes. Readers don't have
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to pause during a rewrite.
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Note for developers: packages that need to read cdb files should
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incorporate the necessary portions of the cdb library rather than
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relying on an external cdb library. (See WWW)
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WWW: http://cr.yp.to/cdb.html
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