Method Delete

engine/db.go:348–379

Delete data according to the key

(key []byte)

// Delete data according to the key
func (db *DB) Delete(key []byte) error {
	zap.L().Info("delete", zap.ByteString("key", key))

	// Determine the validity of the key
	if len(key) == 0 {
		return _const.ErrKeyIsEmpty
	}

	// Check whether the key exists. If it does not exist, return it
	if pst := db.index.Get(key); pst == nil {
		return nil
	}

	// Construct a logRecord to indicate that it was deleted
	logRecord := &data2.LogRecord{
		Key:  encodeLogRecordKeyWithSeq(key, nonTransactionSeqNo),
		Type: data2.LogRecordDeleted,
	}

	// Write to the data file
	_, err := db.appendLogRecordWithLock(logRecord)
	if err != nil {
		return err
	}

	// Removes key from memory index
	ok := db.index.Delete(key)
	if !ok {
		return _const.ErrIndexUpdateFailed
	}
	return nil
}

// Load the data file from disk
func (db *DB) loadDataFiles() error {