1. A method for implementing a docbase management system, comprising: parsing an invocation from an application to build an intermediate form which comprises objects and/or operations of a universal model; converting the intermediate form which comprises objects and/or operations of the universal document model into execution plans; selecting a preferable execution plan from the execution plans which comprises operations on physical storage according to an algorithm based on priorities of the experience rules; scheduling and executing the preferable execution plan; wherein, selecting a preferable execution plan from the execution plans according to an algorithm based on priorities of the experience rules comprises: when there are L experience rules, namely R 1 , R 2. .. R L , and the priorities of the experience rules follow the inequality R 1 >R 2 >. .. >R L , performing the following steps: step a1: initiating an execution plan set with all generated execution plans, setting R i as the judgment criterion to be applied currently, wherein i=1 in the initial status, step a2: determining whether the execution plans in the execution plan set meet R i in turn; marking and deleting an execution plan which does not meet R i from the execution plan set; step a3: if the execution plan set becomes empty, putting the execution plans marked in Step a2 into the execution plan set and determining whether i equals to L; if i equals to L, selecting an execution plan from the execution plan set at random as the preferable execution plan based on priorities of the experience rules; otherwise, adding 1 to i and repeating step a2.