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This is a native Go implementation of cdb, a constant key/value database with some very nice properties. From the design doc:

cdb is a fast, reliable, simple package for creating and reading constant databases. Its database structure provides several features:

Fast lookups: A successful lookup in a large database normally takes just two disk accesses. An unsuccessful lookup takes only one.

Low overhead: A database uses 2048 bytes, plus 24 bytes per record, plus the space for keys and data.

No random limits: cdb can handle any database up to 4 gigabytes. There are no other restrictions; records don't even have to fit into memory. Databases are stored in a machine-independent format.

Usage

writer, err := cdb.Create("/tmp/example.cdb") if err != nil { log.Fatal(err) }

// Write some key/value pairs to the database. writer.Put([]byte("Alice"), []byte("Practice")) writer.Put([]byte("Bob"), []byte("Hope")) writer.Put([]byte("Charlie"), []byte("Horse"))

// Freeze the database, and open it for reads. db, err := writer.Freeze() if err != nil { log.Fatal(err) }

// Fetch a value. v, err := db.Get([]byte("Alice")) if err != nil { log.Fatal(err) }

log.Println(string(v)) // => Practice

// Iterate over the database iter := db.Iter() for iter.Next() { log.Printf("The key %s has a value of length %d\n", string(iter.Key()), len(iter.Value())) }

if err := iter.Err(); err != nil { log.Fatal(err) }