Method Put

engine/db.go:147–173

Put write a key-value pair to db, and the key must be not empty

(key []byte, value []byte)

// Put write a key-value pair to db, and the key must be not empty
func (db *DB) Put(key []byte, value []byte) error {
	zap.L().Info("put", zap.ByteString("key", key), zap.ByteString("value", value))
	// check key
	if len(key) == 0 {
		return _const.ErrKeyIsEmpty
	}

	// check LogRecord
	logRecord := &data2.LogRecord{
		Key:   encodeLogRecordKeyWithSeq(key, nonTransactionSeqNo),
		Value: value,
		Type:  data2.LogRecordNormal,
	}

	// append log record
	pos, err := db.appendLogRecordWithLock(logRecord)
	if err != nil {
		return err
	}

	// update index
	if ok := db.index.Put(key, pos); !ok {
		return _const.ErrIndexUpdateFailed
	}

	return nil
}

// appendLogRecord ethod added lock logic split,
// to avoid batch write resulting in deadlock problems