应该是你的表里面多了空白的行吧?
Dim st As Date = Date.Now
Dim b As New SQLGroupTableBuilder("综合统计","人员")
b.Groups.Adddef("类别")
b.filter="类别 is not null"
b.Totals.Adddef("类别",AggregateEnum.Count,"人数")
b.Totals.Addexp("性别_男","IIF(性别 = '男',1,0)")
b.Totals.Addexp("性别_女","IIF(性别 = '女',1,0)")
b.Totals.Addexp("民族_汉族","IIF(民族 = '汉族',1,0)")
b.Totals.Addexp("民族_少数民族","IIF(民族 <> '汉族',1,0)")
b.VerticalTotal = True
b.Build