mirror of
https://github.com/astaxie/beego.git
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93 lines
2.2 KiB
Go
93 lines
2.2 KiB
Go
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// Copyright (c) 2012, Suryandaru Triandana <syndtr@gmail.com>
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// All rights reserved.
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//
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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// Package leveldb provides implementation of LevelDB key/value database.
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//
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// Create or open a database:
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//
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// // The returned DB instance is safe for concurrent use. Which mean that all
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// // DB's methods may be called concurrently from multiple goroutine.
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// db, err := leveldb.OpenFile("path/to/db", nil)
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// ...
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// defer db.Close()
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// ...
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//
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// Read or modify the database content:
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//
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// // Remember that the contents of the returned slice should not be modified.
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// data, err := db.Get([]byte("key"), nil)
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// ...
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// err = db.Put([]byte("key"), []byte("value"), nil)
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// ...
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// err = db.Delete([]byte("key"), nil)
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// ...
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//
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// Iterate over database content:
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//
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// iter := db.NewIterator(nil, nil)
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// for iter.Next() {
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// // Remember that the contents of the returned slice should not be modified, and
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// // only valid until the next call to Next.
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// key := iter.Key()
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// value := iter.Value()
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// ...
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// }
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// iter.Release()
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// err = iter.Error()
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// ...
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//
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// Iterate over subset of database content with a particular prefix:
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// iter := db.NewIterator(util.BytesPrefix([]byte("foo-")), nil)
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// for iter.Next() {
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// // Use key/value.
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// ...
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// }
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// iter.Release()
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// err = iter.Error()
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// ...
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//
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// Seek-then-Iterate:
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//
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// iter := db.NewIterator(nil, nil)
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// for ok := iter.Seek(key); ok; ok = iter.Next() {
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// // Use key/value.
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// ...
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// }
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// iter.Release()
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// err = iter.Error()
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// ...
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//
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// Iterate over subset of database content:
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//
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// iter := db.NewIterator(&util.Range{Start: []byte("foo"), Limit: []byte("xoo")}, nil)
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// for iter.Next() {
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// // Use key/value.
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// ...
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// }
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// iter.Release()
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// err = iter.Error()
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// ...
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//
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// Batch writes:
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//
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// batch := new(leveldb.Batch)
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// batch.Put([]byte("foo"), []byte("value"))
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// batch.Put([]byte("bar"), []byte("another value"))
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// batch.Delete([]byte("baz"))
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// err = db.Write(batch, nil)
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// ...
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//
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// Use bloom filter:
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//
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// o := &opt.Options{
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// Filter: filter.NewBloomFilter(10),
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// }
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// db, err := leveldb.OpenFile("path/to/db", o)
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// ...
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// defer db.Close()
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// ...
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package leveldb
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