Use The Hierarchical Bitmap Index For A Subset Of The Query

With the rapid development and popularization of database technology. People can storage large number information in database and query a large number of information from database. But an outstanding problem exists while we meet set-valued attributes database, also, querying and indexing set-valued attributes database need high effective index and query method. How to assort the Set-valued attributes database and setup effective index for querying is an imperious problem, this article expound an efficient method-assort hierarchical bitmap index subset querying, which can dissolve the problem talked above, and according test, the method is verified an effective way to accelerate index speed. The main words and achievements we have done as follows:1. Proposed a new index structureBased on the hierarchical Bitmap Index for database.2. Propose a new query processing methodIn this paper, we proposed a new solution which take advantage of the multithread mechanism, utilize the huge-effect index structure built in this paper, from the button of a path expression to the up, to process a subset query simultaneously. To support the multithread mechanisms,3. Presented the key algorithms and their programming codesIn this paper, we presented the key algorithms and their programming codes on how to build the desired index structure and how to query,as article[1] says. Mainly include: the algorithm of parsing database document to build a special index structure, the algorithm of parsing path expression to build the relevant objects and the algorithm of processing a query multithreading simultaneously.The technologies adopted among this paper also have some practical reference values for programmers.4. ExpreimentWe compared the traditional method with our method on the query efficiency on some set-valued database documents of different size in an experiment. Through analyzing the experimental result, we pointed out the remarkable improvement of query efficiency by our method and pointed out the problem still existing in it.