我的报表里面其中一个柱形图配的是这样的数据集, 在PLSQL执行完全没问题,但是配到图表去,图表一直出不来这是为什么?把数据集随意换成这个就能展示:select 1 as mth, 12 as a from dualunion allselect 2 as mth, 15 as a from dualunion allselect 3 as mth, 25 as a from dualunion allselect 4 as mth, 40 as a from dual说明是数据集的问题,但是数据集能执行出结果啊?这是怎么回事?