Abstract: To compress value-list index more efficiently，this paper analyzes the disadvantages of the traditional run-length encode approach，and then presents two corresponding improvements，one is to sort the data table to prolong the 0’s and 1’s in the value-list index vectors，the other is to modify the encoding algorithm to compress the 0’s and 1’s at the same time.Experimental results show that the volume of the compressed file when new approach adapted is only 11.83% of that when traditional approach adapted.

摘要： 为了进一步提高采用游程编码方法压缩值索引的效率，针对原有方法的不足之处，采取了两个改进措施，一是在索引前排序被索引的数据表使得值索引中的0串和1串更长，二是改进现有编码算法使之可以同时压缩0串和1串。实验结果表明，采用改进后方法压缩值索引形成的压缩文件体积仅为采用原有方法时的11.83%。