43 results about "Index compression" patented technology

A method for compressing index pages in a database system is provided. The database system includes a table, and the table includes table columns. The method includes: providing an index associated with the table, wherein the index is stored on at least one index page of the database system, and wherein the index comprises index columns related to a part of the table columns; providing a first sequence of the index columns; providing a second sequence of the index columns; arranging the index columns stored on the at least one index page according to the second sequence; performing a prefix compression on entries of the at least one index page; and accessing the index using the first sequence of the index columns.

The invention discloses a quantum safety communication method based on synchronous random number information base information retrieval, which avoids channel loss and noise, has high efficiency, is safe and reliable, and is low in cost. The method comprises the following steps of: 1) establishing a synchronous random number information base with large data volume at a sending end and a receiving end of a quantum communication system; 2) determining the unit length of information units according to the data volume of the information base at the sending end, and establishing an information maintenance table for the information base simultaneously; 3) preprocessing communication data at the sending end; 4) searching an information unit which is the same as the preprocessed communication datain the information base at the sending end, and recording the searched index communication data; 5) compressing the index communication data to acquire index compressed data, and sending the index compressed data to the receiving end in a classical communication mode; 6) performing reverse operation on the received index compressed data by using the receiving end; and 7) updating the information base.

The embodiment of the present invention discloses a vertex index compression and decompression method, device, and computer storage medium; the method may include: according to the set difference range, the elements in the vertex index array are calculated according to the difference between adjacent elements The value is divided into one or more original index segments, and the number of vertex indices of each original index segment and the number of bits corresponding to the maximum difference between adjacent vertex indices in each original index segment are obtained; for each original index Fragment: Keep the first vertex index data unchanged, replace the subsequent vertex index data after the first vertex index data according to the difference between the adjacent vertex index data, and obtain the compressed index fragment corresponding to each original index fragment; All compressed index segments, the number of vertex indexes in each compressed index segment, and the number of bits corresponding to the maximum difference between adjacent vertex indices in the original index segment corresponding to each compressed index segment are in accordance with the original index segment The order of divisions is transferred to the GPU for storage in video memory.

Systems, methods and computer program products for compression of database indexes are described herein. A system embodiment includes a sequence determiner to scan a database index and to determine a start of a range and end of a range of consistently changing values in one or more index pages of said database index and an index updater to update said database index based on a sequence determined by said sequence determiner, while suspending writing of one or more values that lie within start of said range and end of said range of values. A method embodiment includes scanning an index, determining a pattern of changing values in one or more index pages of said index and selectively updating said index based on said determining step to minimize index insertions. The method embodiment further includes determining a start of a range of values and an end of said range of values in an index page, setting appropriate bits to identify said start of range of values and end of range of values, determining if an entry to be inserted can appended to at the end of said range of values, and compressing said index by suspending writing of one or more values that occur between said start of range of values and said end of range of values.