Data retrieval method

摘要

An hierarchical data retrieval method for retrieving an hierarchy of data from a first store is described. The hierarchy of data comprises one or more items of data of a first level, at least one of which is associated with one or more items of data of a second level. The method comprises: i) retrieving from the first store the items of data of the first level only; ii) displaying the items of data of the first level to a user; iii) retrieving from the first store the items of data of the second level associated with one of the items of data of the first level in response to a user request indicating that item of data of the first level; and, iv) displaying the items of data of the second level retrieved in step (iii) in addition to the items of data of the first level.