A simple fast method is given for sequentially retrieving all the records in a B tree. A file structure for database is proposed. The records in its primary data file are sorted according to the key order. A B tree ...A simple fast method is given for sequentially retrieving all the records in a B tree. A file structure for database is proposed. The records in its primary data file are sorted according to the key order. A B tree is used as its dense index. It is easy to insert, delete or search a record, and it is also convenient to retrieve records in the sequential order of the keys. The merits and efficiencies of these methods or structures are discussed in detail.展开更多
随着大数据时代来临,各行各业存在着数据孤岛现象和数据被篡改的风险,无法保障跨行业数据溯源的完整性和可信性。针对上述问题,首先,设计一种新型的BT_Merkle树区块存储结构,提出基于“私有链+联盟链”的双链溯源算法,从而实现跨行业数...随着大数据时代来临,各行各业存在着数据孤岛现象和数据被篡改的风险,无法保障跨行业数据溯源的完整性和可信性。针对上述问题,首先,设计一种新型的BT_Merkle树区块存储结构,提出基于“私有链+联盟链”的双链溯源算法,从而实现跨行业数据共享;其次,利用布隆过滤器和B+树分别为离散性和连续性属性建立索引,从而实现对不同属性关键字的溯源。通过实验证明,在保证数据不被篡改及不出域的前提下,与BMerkle树(Bloom filter and Merkle tree)相比,BT_Merkle树在联盟链和私有链上的溯源效率都更高,并能够快速查找交易记录,为跨行业数据的溯源提供了理论及实践依据。展开更多
文摘A simple fast method is given for sequentially retrieving all the records in a B tree. A file structure for database is proposed. The records in its primary data file are sorted according to the key order. A B tree is used as its dense index. It is easy to insert, delete or search a record, and it is also convenient to retrieve records in the sequential order of the keys. The merits and efficiencies of these methods or structures are discussed in detail.
文摘随着大数据时代来临,各行各业存在着数据孤岛现象和数据被篡改的风险,无法保障跨行业数据溯源的完整性和可信性。针对上述问题,首先,设计一种新型的BT_Merkle树区块存储结构,提出基于“私有链+联盟链”的双链溯源算法,从而实现跨行业数据共享;其次,利用布隆过滤器和B+树分别为离散性和连续性属性建立索引,从而实现对不同属性关键字的溯源。通过实验证明,在保证数据不被篡改及不出域的前提下,与BMerkle树(Bloom filter and Merkle tree)相比,BT_Merkle树在联盟链和私有链上的溯源效率都更高,并能够快速查找交易记录,为跨行业数据的溯源提供了理论及实践依据。
