The Research Of Search Engine Based On Ajax

With the running up of Web information, Search Engine as a kind of new technology has been developed gradually since 1995.That is extremely difficult for users to look for information in vast data ocean. So Search Engine is the exact technology appearing in order to solve this problem. It finds and collects information by a certain devices, and then comprehends abstracts, organizes and handles these pieces of information. It also serves as information navigation. Therefore, Search Engine technology has become the studying and developing target of the industrial and academic field of computer.Search Engine is made to achieve the goat of storage, organization and access of the information items on the network. Search Engine can be used to locate a huge number of information on network as well as some unknown information can be quickly found. Internet search engine is the core of information retrieval technology. At present, Search Engine that is widely used on the Internet, including the Chinese search engines, has no less than ten, such as Google, head of the general purposes search engine, and various types of vertical Web search tools based on industry classification. However, there are still a long distance between the Chinese search engine and its similar products abroad, such as low coverage, the not high correction rate, the bad accuracy of retrieval, slow updating, unable to controlling the dynamic changes of network information, and difficulty on control and management of the content.The history and present status of search engine is analyzed. In accordance with the weakness existed in current search engine, the Ajax based search engine is constructed from the perspective of Ajax techniques with combination of XML data sets. Traditional web service is based on Request-Response mode just only once. Under Ajax technology, the Client could request data from Server one more times. After download the necessary data and main control code from the Server, user can read the main information, but the transmission is continued in backstage, the Ajax engine keeps on send requests to the server in order get more information. When new information arrived, old data in the WEB page would be replaced by DOM without refresh screen.It makes Search Engine more quickly by improving the PageRank algorithm and eliminating the duplicated pages in the index. And Search Engine can get more information form web pages through culling the dates of Ajax.