Data lineage includes two parts : ( 1 ) the set of source data items which exactly produces the warehouse data item ; ( 2 ) the processes which contribute to the set of source data items 数据志包含两个部分:起始数据集和作用在该数据集上的数据处理过程。获取数据志的过程称为数据志跟踪( datalineagetracing ) 。