The Application and Research of the Spanning Tree in the Project Based on Database

The first level of material´s classification information by means of tree structure is added up to thousands of kinds, and dozens of levels in depth. Therefore, it is rather hard to make the spanning tree. By comparing of three methods of spanning tree, by using the median compositor cardinal number, recursive method, loop method, it is found that the efficiency of their existence spanning tree is not high, and the depth of spanning tree is restricted and so on. This thesis puts forward a strategy by which material´s classification information is read in a database in advance, and then sorts this information in the database. Finally based on the code of the ranking information, the spanning tree is formed by means of constructing tree algorithm. The result of the experiment shows that the strategy not only resolves the limi-tation of tree structure in level and depth, but it also improves the efficiency of the spanning tree.