Abstract:Under large amount of data the union operation makes data paging very slow, how to improve the performance of data paging efficiency becomes an import issue for MySql. This paper proposes a new data paging algorithm from analysis of union operation in MySql data paging method's advantages and disadvantages, and the key factors affects the speed of the data paging. By avoiding union operation in multi-table query and using indexes it improves query efficiency and reasonable. The experimental results confirms that the optimized query methods in pagination operations could significantly improve the speed.