Documentation ¶
Overview ¶
Package memorydb implements the key-value database layer based on memory maps. 实现了所有接口的内存数据库,只用来进行测试 简而言之就是实现了KeyValueStore接口
Index ¶
- type Database
- func (db *Database) Close() error
- func (db *Database) Compact(start []byte, limit []byte) error
- func (db *Database) Delete(key []byte) error
- func (db *Database) Get(key []byte) ([]byte, error)
- func (db *Database) Has(key []byte) (bool, error)
- func (db *Database) Len() int
- func (db *Database) NewBatch() ethdb.Batch
- func (db *Database) NewIterator(prefix []byte, start []byte) ethdb.Iterator
- func (db *Database) Put(key []byte, value []byte) error
- func (db *Database) Stat(property string) (string, error)
Constants ¶
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Variables ¶
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Functions ¶
This section is empty.
Types ¶
type Database ¶
type Database struct {
// contains filtered or unexported fields
}
Database is an ephemeral key-value store. Apart from basic data storage functionality it also supports batch writes and iterating over the keyspace in binary-alphabetical order.
func New ¶
func New() *Database
New returns a wrapped map with all the required database interface methods implemented.
func NewWithCap ¶
NewWithCap returns a wrapped map pre-allocated to the provided capcity with all the required database interface methods implemented. 初始化时指定了Cap大小
func (*Database) Close ¶
Close deallocates the internal map and ensures any consecutive data access op failes with an error.
func (*Database) Compact ¶
Compact is not supported on a memory database, but there's no need either as a memory database doesn't waste space anyway.
func (*Database) Len ¶
Len returns the number of entries currently present in the memory database.
Note, this method is only used for testing (i.e. not public in general) and does not have explicit checks for closed-ness to allow simpler testing code.
func (*Database) NewBatch ¶
NewBatch creates a write-only key-value store that buffers changes to its host database until a final write is called. 创建一个只写的缓存区域,
func (*Database) NewIterator ¶
NewIterator creates a binary-alphabetical iterator over a subset of database content with a particular key prefix, starting at a particular initial key (or after, if it does not exist). 创建一个Iterator对象,内部按照字典顺序保存了符合规则的key和value