源数据集A:
date name value
20130213 x1 3.6
20130213 x2 5.6
20130213 x3 7.6
20130213 x4 1.6
源数据集B(一年的日期):
date
20130213
..............
20140213
目标数据集C:
date name value
20130213 x1 3.6
20130213 x2 5.6
20130213 x3 7.6
20130213 x4 1.6
...........................
20140213 x1 3.6
20140213 x2 5.6
20140213 x3 7.6
20140213 x4 1.6
怎么在DATA步实现,谢谢!